losing ground

[Cameron]

I am now worse off than I started and I am not sure why (went back to an original bin file to make sure I hadnt gotten carried away in my edits.

the engine will now run nicely for about 30 seconds then die.  I cant seem to figure out why.  with the air cleaner off I can see it is getting fuel.  I am not entirely sure what I am l am looking for in the data logs, but nothing is jumping out at me. 

here are 2 csv's.  wtf3 is just idling with my base idle set at 750.  wtf4 is with my foot on the throttle keeping the idle higher.  

any advice welcomed.  was supposed to take it out tomorrow and based on my drive yesterday, my tune was ok, not great but ok.  today it is not going anyplace tomorrow..

[Bill Van Vlack]

Have you tried changing the module in the distributor?

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[Cameron]

no, bill, I have not.  it is the coil in the top of the cap, right?  that what you referring to?

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[Cameron]

is there a 'reason' it would get spark for ~30 seconds (or longer, last start was almost 1 minute 30) then die?  I guess the question is, do they fail 'intermittently'?  or should it just be "failed" and not start at all?

[Bill Van Vlack]

No; It's below the rotor and looks like this:  Sort of. Are you doing spark control with the EBL?  As I understand it, the module can fail in oh so many ways. Always carry a spare.

On Sun, Aug 27, 2023 at 11:54 AM Cameron <cbi...@gmail.com> wrote:

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[Larry Davick]

The ignition module is inside the distributor on the plate where points used to be, way back when.  They are prone to fail and are easy to swap out.  

Larry Davick

1976 Palm Beach

Fremont, Ca

[Cameron]

my distributor is new.  so that module is also new, right?  I didnt have to swap anything from the old dist to the new dist besides the cap..

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[Cameron]

yeah, that module is new on my distributor.  went an looked at my old dist and see that part, and this one has a brand new module.  

losing spark does seem like a possibility, though.  it seems to have fuel, it has air.  so, it has to be spark - right?

is there a history of the coils failing on these things?

[Jon Roche]

Hook up the timing light.   Route the wires so they cant  melt on exhaust or get caught by pulleys and fans.  

Zip tie the trigger on.   And then lay it on floor where you can see flash when you drive/run.  

That visual  will give you some idea on if spark is failing. 

What seemed really odd.  Is when you first started this process.  You had a hard time getting a timing light to register right?????   That is most unusual.   I wonder if alternator is tossing out bad frequencies or something electrical is really interfering with the whole system??

On Aug 27, 2023, at 2:16 PM, Cameron <cbi...@gmail.com> wrote:



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[James Hupy]

New is only New. Not necessarily good, particularly when hot. If you do not have the heat sink compound under the module, it will go "toes up" in very short order. I never, ever use any module but a genuine GM one. Aftermarket stuff is truly not up to GM standards, especially in heat resistance. I always carry a known good spare.

Jim Hupy

Salem, Oregon

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[George Beckman]

I should have mentioned coil in my module note. Yes, bad modules take out coils and coils that are failing often fail as they get warmer—hot.

On Aug 27, 2023, at 12:15 PM, Cameron <cbi...@gmail.com> wrote:

losing spark does seem like a possibility, though.  it seems to have fuel, it has air.  so, it has to be spark - right?

is there a history of the coils failing on these things?

---------

Best Wishes,

George
gbec...@graestone.org

[Cameron]

Thanks George, the pieces are coming together.  I replaced the coil (and cap and rotor) and things seem to be better.  Timing light even works.

Agreed on the heat as an exacerbating factor.  Always seemed to run worse when at operating temperature.

Gonna try another test drive and hope I’m still going camping tomorrow!

Thanks for all the input!

Cameron 

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[Larry Davick]

Considering the title of this thread wouldn’t it be ironic if there were an intermittent grounding issue for the module?

Larry Davick

1976 Palm Beach

A Mystery Machine

Fremont CA

[George Beckman]

Best wishes with it!

On Aug 27, 2023, at 2:32 PM, Cameron <cbi...@gmail.com> wrote:

Gonna try another test drive and hope I’m still going camping tomorrow!

[Cameron]

for those following along (and helping!) from home I wanted to give a status update.

the drive yesterday was eventful.  mid intersection, rv dies, restart and the throttle sticks!  that was a nightmare!  thank the dear lord for kind people, a gentleman helped push me out of the intersection and I began to troubleshoot.  when the engine gets hot, seemed to flex that plate and stuck the butterflies open.  I will keep this brief, to say that I got home, pulled the TBI, resealed it, and retorqued it.  I think that solved that issue...  I think mechanically im ok now.  I think it is all computer work that is left.

the main tuning at this point I have been doing is to the AE (acceleration enrichment) tables.  this seems to be helping.  it is dying less at start up from stop lights.  (Jon, would like to look at that BIN you said would would send.  see where your AE tables are).  in park takes the throttle fine, but underload, wants to die.  I can work around it by riding the brake a bit while increasing throttle.  I know something in my tuneup is still off.

I did have an interesting, new issue.  I had just gone up a grade, not overly long, maybe a minute or two climb, speed roughly 40.  on the down side it started backfiring!  my wife in the just in case follow vehicle could see flame out the tail pipe.  any suggestions on that one!

thanks for all the help and advice.

Cameron

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[BruceHislop]

Cameron,
I went back over your email to the Group just to see what EFI system you have.  The stalling off-idle reminds me of the issues I had when I first got my Howell system.  The problem was that Holley (the TB they used) changed from 80 pph injectors to 60 pph.  Therefore the AFR from the tables was lean and also the enrichment was also lean.  I was having problems with stumbling etc and  no amount of fooling with the fuel tables would fix it.  Once I discovered the injectors were smaller, the fix was to up the fuel pressure to get the smaller injectors to flow at 80pph.

It seems you have a Affordable Fuel Injection system.  Do you know if they supplied a TB from a 454 with 80pph injectors? Or was a smaller TB that they bored out?... and if so what are the injector flow rates?  Did they tell you the fuel pressure you need to run?

If your injectors are not flowing at 80pph, then that is going to throw all the tables off.  You need 80pph flow rate so that the AFR does not lean out at wide open throttle.  Smaller injectors can be used, but at a higher fuel pressure to get them to flow 80pph.

Bruce Hislop

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[Cameron]

hey Bruce,

unfortunately I got 'blank stares' when asking the #/hr question.  when I asked about the "flow rate" the answer I got "variable based on input from sensors".  

I do think the AFI guys know what they are doing (I had one very technical conversation when I was troubleshooting my harness issue when first getting started - the red/blue connector vs black/black connector..).  so I am likely not asking the question correctly.  can you coach me on what to ask?

it is a rochester tbi.  the form I filled out on the AFI site was for a 455 olds., so they "should know" what my intended installation was.

thanks!

Cameron

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[Bill Van Vlack]

Here's how to tell which TB and injectors you have.....

Throttle Body: 

https://throttlebodyinjection.com/GM_TBI-220_T8-164R.htm

 Injectors: 

 https://www.thirdgen.org/forums/tbi/760190-tbi-injector-identification.html

https://www.thirdgen.org/forums/diy-prom/209440-tbi-injector-info.html

 

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[Terence Taylor]

Cameron, when I installed my EBL, I had to pley with AE a lot to get it to not stall on acceleration. I think you are on the right track.

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[Cameron]

Terrence,

Can you take a screenshot of the 4 main tables?

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[Terence Taylor]

I no longer have my GMC, so no.

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[Cameron]

Got it, thanks 

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[Cameron]

Hey Bill,

looking at the https://www.thirdgen.org/forums/tbi/760190-tbi-injector-identification.html page;

and this entry "Dark Red/Dark Blue big block pickup 90 lb/hr GM 5235231 *RPD"

so, I have 90lb/hr?

however, for conflicting information;

there are also comments about common part numbers, but mine isnt on that list, it is difficult to see, but I think it is 17093030 (that last 3 is not stamped well, could be a different number).

a quick google search for that part number found "17093030 Remanufactured Throttle Body | GMC Chevrolet 5.7L 1993-1995".

Thanks!

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[MICHAEL ORLANDI]

Didn’t you tell us you were using a bored out (1 11/16)4.3,5.0or 5.7  throttle body with injectors that needed 20 lbs fuel pressure? 

Get Outlook for iOS

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From: gmcm...@googlegroups.com <gmcm...@googlegroups.com> on behalf of Cameron <cbi...@gmail.com>
Sent: Monday, August 28, 2023 5:07:00 PM
To: gmcm...@googlegroups.com <gmcm...@googlegroups.com>
Subject: Re: [GMCMH-EFI] losing ground

 

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[Bill Van Vlack]

The colors are not on the connectors, but on each side of the round part with bites out of them that is between them. Your photo looks like blue/black or 80#/hr injectors. At least I think that's black.

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[Cameron]

it's dark blue.  so, in theory, I shouldnt be lean.  I am going to keep messing with the AE tables and hopefully get where I need to be.

(Michael - no, that wasnt me.  I just bought a kit from Affordable EFI and not entirely sure what I got..)

thanks!

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[Bill Van Vlack]

I notice in your datalog that PSI-5 is reporting around 2 psi,WB02 is reporting 7.5, NB02 always around 450 or above, and that there is no column for the Closed Loop flag.

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[Cameron]

pretty sure on that 2 is not psi it is volts.  my fps is a 0-5 volt sensor, for 0-30 psi.  so, I think 2 psi = 30/2=15 psi.

I dont have a narrow band sensor, I have a wide band sensor on adc channel 01.

I think I removed the CL column for the graph, since it was not something I was graphing (sorry for that confusion..)

Thanks!

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[Bill Van Vlack]

If you have it set up this way, it's psi.

Pretty sure the EBL needs an NBO2 sensor to work properly.

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[Cameron]

it needs a NB *and* a WB sensor?  that could definitely be a problem..  I thought it was one or the other!

I do have it set up like you do;

 

I was just thinking there was no way I only had 2psi, so it expected me to do the math...

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[Bill Van Vlack]

As far as I understand, the EBL requires the NBO2 to do fuel control, and adding the WBO2 gives a real AFR number for display and an option for WB Learns but it does not affect real time fueling calculations. .

My FP setup reports ~12, so not volts. The FP sensor is reporting either pump pressure at the TB if it's lower than what the fuel pressure regulator is set for, or regulated fuel pressure.

Maybe install a temporary FP gauge to verify. At 2 psi you should not be seeing any return fuel, so you could disconnect and route the return line into a bucket for a rough check.

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[Jon Roche]

It NEEDS a the narrow band.     Optional and reccomend  to add the wide band. 

On Aug 29, 2023, at 11:43 AM, Cameron <cbi...@gmail.com> wrote:



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[Jon Roche]

I should add.   Narrow band should be part of harness.  If headers then you probably want a “heated one”.  If manifolds i think heated or not heated works.  

On Aug 29, 2023, at 12:19 PM, Jon Roche <lqqk...@gmail.com> wrote:



[Cameron]

wow guys.  I totally thought I could just replace it.  I just sent a note to Bob at Dynamic but it sounds like very interesting misunderstanding on my part!

thanks!

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[Bill Van Vlack]

Heated Narrow Band Sensor:   https://www.amazon.com/Bosch-13077-Oxygen-Sensor-Fitment/dp/B0009IK7YW

Connect heater power to 12V ignition.

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[Cameron]

thanks!

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[Cameron]

hey, just got this back from Bob;

"No need for both, but it is better to have both."

I'm a little bummed on that answer.  I was hoping this was my 'easy button'...  

I was thinking of buying a NB sensor where I am staying and try the drive home with it, *instead* of the WB (since, I dont currently have 2 places to mount sensors in my exhaust).  think I should try that?  or think I am "ok" down my current path with the WB and the AE tables (and add the NB later)?

opinions welcomed!

Cameron

[Bill Van Vlack]

This drawing titled EBL ECM Wiring from Dynamic EFI shows a NBO2. It does not show a WBO2 sensor. Other pages on that site describe how to install and use a WBO2 to use for learning.

When I got a harness harvested from an 80's GM, it had an NBO2 connector. There are no stock connections for a WBO2 on a stock GM TB ECM.

If you asked whether one needs both WB and NB sensors, I might answer "No need for both, but it is better to have both."

Odds are you'll have better luck with the NBO2. Connect it via the ECM to harness connectors, not via the ADC port.

Bill

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[Cameron]

thanks bill!  i'll go to the parts store and pick one up today.

Cameron

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[James Hupy]

I use Denso brand. Part # 234-1000. They have been very reliable for me.

Jim Hupy

Salem, Oregon

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[M B]

Back to the injectors.  Keep in mind that affordable told me if they don’t have the 80-90# injectors they will replace the spring in the smaller injectors to increase flow. So the color of your injectors may not be a good indicator of flow. You could take them to a local shop that repairs/cleans injectors to get them to measure the flow AND make sure they are working correctly. 

[Cameron]

so, there has been improvement in my experience.  here is where I currently stand;

I used a half way point between my AE tables and Jon's.  this definitely helped things.  so, I think I am on a pretty good track there.  I also put a NB sensor back in and will install the WB sensor the next time I have the opportunity to work on it.

one thing happened today and I would like your opinions.  on the way back, at speed (but not under acceleration) the engine died.  so, while coasting along at (what ever speed I was going when it died, once on the fwy at ~60) I would - carefully - put the transmission in neutral, turn the key off and on and restart it.  generally starts right back up and runs fine.  it died 3 times in a 45 minute drive.  

my guess is this;  when I had a vacuum leak the engine was getting air from the leak and was running lean.  now that I have closed down the leak I think I need to open up the butterflies.  I think it is getting air from the IAC, but fuel isnt getting past the butterflies.  so, I just tried to open up the butterflies a bit and started the engine and the IAC is at ~12 steps and the TPS is at .3v.  I think both of these settings are lower than the prefered settings.  any thoughts?

thanks!

Cameron

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[Bill Van Vlack]

12 steps at warm idle is fine. Other times, it can be anything. Here is Bob R's intro for the IAC logic paper..

"Along with controlling the idle speed, the IAC is in use while cruising and accelerating. It is used in the anti-stall process and the DFCO process. As part of the fueling routines, additional fuel is added whenever the IAC is retracted. "

At idle, the TPS volts should be zero. I've never had to do it, even though I had to adjust the throttle screw slightly to bring my idle IAC down to the 12 steps it sits at present. Coach idles great.  I believe one of the mounting bolts is slotted to allow adjustment of the TPS to 0v at idle.

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[Bruce Hislop]

Bill, the TPS voltage should be just above Zero at idle.  Something around 0.5 V is good.  The EBL wants to always see something above Zero and below 5V.  That will show the TPS circuit is complete.  If it's at Zero it will report an error (lost 5v line) or if at 5v it will think you lost ground to the TPS or a faulty TPS in either condition.

Bruce Hislop

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[Bill Van Vlack]

Bruce,

 I wrote 0V, but meant 5V! Or to be more accurate, realized it when you replied. Thanks!

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[Cameron]

thanks guys!  I had some conflicting priorities get in the way of reading my email.

any thoughts on dying at cruise?  thing my guess is bordering on possible?  I wont be able to drive the coach for a couple weeks so just preparing my next ebl update..

thanks!

Cameron

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[James Hupy]

If you were moving at 60mph with some throttle opening OTHER THAN IDLE and your engine quit without any advance indications that it might be running out of fuel, then I would certainly look at your ignition module and/or high tension coil. If you are using ANY OTHER ignition than a GM HEI, I would strongly recommend to yank that sucker out of there and replace it with a KNOWN TO BE GOOD, GM HEI. Then re test and see if you still have the problem. If you have no spark, your fuel injection will NOT spray fuel. 

Jim Hupy

Salem, Oregon

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[Cameron]

thanks Jim.

I *just* replaced the coil, I *think* it is good.  unfortunately with the WB sensor removed (to put the NB back on) and my FPS not giving good readings I am shooting in the dark a bit.  next time I am up with the vehicle I will get the WB sensor back on and hopefully do some troubleshooting on the FPS.  I am grabbing my 5v from the power going to the pumps to power my FPS, maybe the best bet is to get a separate 5v power supply for it..  probably shouldnt mess with the power to the pumps and might help get more accuracy out of my sensor.  was just too tempting with that 5v power running right past my sensor to not use it..

making my list for next tests.

thanks!

Cameron

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[Johnny Bridges]

How many zillion EFIs were shipped?  Enough they're easy  and reliable within limits.  Just make sure of the proper ones - wire colors - for the OLDs engine.

--johnny

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[Bill Van Vlack]

Not sure why you're running the fuel pump(s) on 5v power. Where does that 5v supply come from?

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[Cameron]

you are totally right, bill.  that wouldnt be 5 volt power.  it is the fuel pump power coming from the ECM.  (that could definitely explain why I am not getting good readings from it!  yes, add to my list of silly mistakes..)

looking around for how to get 5v power to the FPS.

suggestions welcomed.

Thanks!

Cameron

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[Bill Van Vlack]

12v dc to 5v dc power supply:

https://www.amazon.com/DROK-Electric-Converter-Step-Down-Regulator/dp/B00C63TLCC/ref=sr_1_5?crid=1TRK5RBLLAAGH&keywords=12v+to+5v+power+supply&qid=1693930082&s=industrial&sprefix=12v+to+5v+power+supply%2Cindustrial%2C170&sr=1-5

I added a small terminal block for the 5v side in case I wanted to add additional sensors. I also added one for 12V IGN distribution.

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[Cameron]

thanks!

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[Larry Davick]

Cameron,

Please forgive my ignorance, but I thought your response to Jim might be telling.  You note that you’ve just replaced the coil, but he also suggested replacing the ignition module.  My knee jerk diagnosis was the module.  

Have you recently replaced that, or verified its connection, particularly the ground?

Work gets in the way of my whole day and I haven’t given this the attention I should before posting so apologies in advance!

Larry Davick

1976 Palm Beach

Fremont ca. 

On Sep 5, 2023, at 8:36 AM, Cameron <cbi...@gmail.com> wrote:



[Jon Roche]

Cameron.   I would

Concentrate

On getting the narrowband situated.  

The wide band installed and working. 

And also need to get that fuel

Pressure working.  

Having those working will help you diagnose the quit at speed issue.    I would not want to start guessing until I can see if your loosing fuel

Pressure.  

The wud can answer lots of questions.  

On Sep 5, 2023, at 10:36 AM, Cameron <cbi...@gmail.com> wrote:



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[Cameron]

No problem Larry, I have been asking a lot of questions here and it is very easy to have missed it in my learning process.

I replaced the distributor which came with a new ignition module.  I do understand that "new" is not entirely indicative of "good", but since I have been learning quite a bit about the intricacies of this install, I will continue to question myself first.  so far, all the problems have been with me not anything I have purchased..

Cameron

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[James Hupy]

Ah, no, my suggestion was to replace the entire distributor, but, alas I failed to make myself clear. But, only if he had another distributor that was NOT a GM HEI in his coach.

Jim Hupy

Salem, Oregon

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[Cameron]

so, I am looking at my datalog and seeing some consistent output in the 3 different 'events' on my way home.  each time the following thing happens at the time of the event.  it is the same for all 3.  some other consistencies, but I think the following are pretty telling;

I essentially looked through my logs for where the RPM dropped to 0 while speed was > 0.  each time;

 + mph momentarily drops to 0 (each time at speeds btw 35 and 50, temp goes to 0, then a few fractions of a second later, it is back recording speed)

 + tps drops to 0 - there is no way I could have pulled my foot off the gas so quickly, not knowing the engine would die

 + IAT goes to -40 - essentially no sensor

 + I/C goes to -40 (I dont know what this I/C stands for, but it also goes to -40 momentarily)

to me, it looks like my system is spontaneously rebooting..  if the system were recording, the speed would continue to register, my foot would be where ever it was for at least a second while my brain caught on that the engine was dead - maybe even increase, since I would first think I was losing power and try to increase the gas.  and, well - temperature doesnt change that fast.

thoughts?

Cameron

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[Jon Roche]

Does the run time reset to zero? On your data log?

On Sep 5, 2023, at 4:15 PM, Cameron <cbi...@gmail.com> wrote:



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[Cameron]

no,  it only resets to 0 after I key off the ignition and restart then engine (my process; engine dies, put in neutral, key off ignition, key on ignition and restart).

Cameron

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[MICHAEL ORLANDI]

It looks to me that you are loosing the ground or the ECM is defective. Do you have a recording DVOM or an oscilloscope? I remember the same type of problem on a car in the shop that I was working on. I had to restring the sensor ground  Circuit . Check the ground ,reference and sensor outlets. You will need some type of recording voltage device.ECM data is not reliable for this test, too slow of a refresh rate.

Sent from my iPhone

On Sep 5, 2023, at 2:19 PM, Cameron <cbi...@gmail.com> wrote:



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[Cameron]

hmm.  no, unfortunately I do not have anything to record the voltage.   unfortunately, a quick google search on a recording voltage meter puts them out of my price range.  I was *very* careful on the ground connections.  I have had experience with how important they are. 

I sent a similar note to Bob at Dynamic about what I was seeing in the logs.  I will update this group with his response if he gives me a way to troubleshoot the experience.  

any thoughts on what Jon mentioned?  "did the timer reset at the time of the 'event'?" to which my answer was "no".  that does call into question my hypothesis.  if the system lost power (or ground) would the timer also reset?  my inclination would be "yes" and that maybe my hypothesis is not accurate.

Thanks!

Cameron

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[MICHAEL ORLANDI]

You might just try restringing the sensor ground Circuit.  Use new connector pins to the ECM and all branch circuits. Solder all connections and at terminal pins. Lay that wire over the existing harness . Then go drive it. In my time as a GM tech I have found a lot of terminal/ connection problems.

Get Outlook for iOS

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From: gmcm...@googlegroups.com <gmcm...@googlegroups.com> on behalf of Cameron <cbi...@gmail.com>

Sent: Tuesday, September 5, 2023 4:18:55 PM

To: gmcm...@googlegroups.com <gmcm...@googlegroups.com>
Subject: Re: [GMCMH-EFI] losing ground

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[Jon Roche]

That was my thinking.   If timer resets.  Then it has lost ignition voltage.    In your case it has not lost the ign. Volts. 

I am not sure if that also means it has not lost 12v power feed also.

And that does not rule out that the distributor has not lost spark or voltage.  

On Sep 5, 2023, at 6:19 PM, Cameron <cbi...@gmail.com> wrote:



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[Bruce Hislop]

If you shut OFF the ignition (Ignition power is lost) I'm sure the Run Timer is not reset, the logging continues when you restart the Ignition.

Now if you lost Battery Positive power but still had Ignition power, I'm not sure what happens then.

The sensors going to -40 and zero TPS indicates a loss of 5V power, not ground.

Intermittent operation can drive a fellow nuts trying to troubleshoot.

Bruce Hislop

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[Bill Van Vlack]

I understand that the FP sensor power was teed off of the fuel pump feed. That would have fed 12v to the 5v terminals of the FP sensor. Presumably all of the other sensors that needed a 5v supply were getting their supply from the ECM internal 5v supply.

Cameron,

 Maybe you can forward a copy of the datalog when this happens. If you play back the datalog, you will see the status of IGN and FP voltage when the engine shut down.

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[George Beckman]

I agree 100% with Jim. A sudden stop doesn’t sound like fuel. You might consider the ignition switch itself. Not up by the key, but on the steering column down by your feet. If you do replace it, there are some write-ups about it. Ordering one for a pickup won’t work without some trickery. It will blow a fuse instantly. 

Our coach stopped running at 65 last time we were out. That turned out to be a battery cable. I had just replaced the engine. Everything was tight, but no dash/ignition juice. I always thought if that happened, the alternator would keep you going. Apparently when it no longer sensed the battery, it stopped charging. Loosen-wiggle-tighten (luckily got to an off ramp) and "all the little lights started blinking again."

On Sep 5, 2023, at 8:23 AM, James Hupy <james...@gmail.com> wrote:

If you were moving at 60mph with some throttle opening OTHER THAN IDLE and your engine quit without any advance indications that it might be running out of fuel, then I would certainly look at your ignition module and/or high tension coil. If you are using ANY OTHER ignition than a GM HEI, I would strongly recommend to yank that sucker out of there and replace it with a KNOWN TO BE GOOD, GM HEI. Then re test and see if you still have the problem. If you have no spark, your fuel injection will NOT spray fuel. 

[Cameron]

each time it ties in a WUD replay, it never shows losing ignition.  2 out of the 3 times, the FP doesnt move (the first time it drops very quickly and comes back - with in the same second on the replay)

one thing I am just now understanding in the data log is the Gr field.  I didnt know what it meant so didnt include in my earlier email.  while watching the WUD I noticed that the gear selector went from D to OD each time it died. now, I understand that Gr is "Gear".  and each time it dies the selector goes from Drive to Over Drive.  is that Interesting?

Thanks!

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[Bill Van Vlack]

Cameron,

  I think the gear field values you are seeing are a symptom, not a cause.,since the EBL does not have an input pin for that field.

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[Cameron]

thanks, that makes sense.

Bob at dynamic is also suggesting an ignition switch issue.  im a bit hesitant to start down this path..  (was begining to think I knew something about the ebl, now another thing I dont know anything about..)

Cameron

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[Jon Roche]

Ignition switch is fairly inexpensive, and pretty easy to replace.  

But i would maybe rig up a test light before i swapped the switch.       See if you are loosing power or not.  

Seems to me that there is getting of variables going on with how the 5v power and 12v power for sensors and ebl are all hooked up. 

On Sep 6, 2023, at 10:42 AM, Cameron <cbi...@gmail.com> wrote:



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[Bruce Hislop]

Looking at the wiring diagram, 5v is only supplied to the TPS and MAP sensors. The other sensors just pull to ground.  But if the ground was faulty, you would see the readings go high, not low.

Dynamic EFI's wiring diagram shows the MAP sensor has it's own dedicated ground back to the ECM.  The TPS shares a ground pin with the CTS and IAC.

I believe your kit came from Affordable EFI, so not sure if they wire the same way.

I would try a switch between the battery and Ignition power.  Since it acts regularly you can switch it On and see if the issue disappears

M

Bruce Hislop

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[Bill Van Vlack]

Going down the road and the engine quits. Cycle the IGN switch and the engine starts and runs.

If the engine quits because IGN power is lost, the gauges would drop out, so look at the gauges before cycling the ignition switch. If they're not reporting it's something between the BAT power to the IGN switch and the IGN bus, if they are reporting, it's the ECM or something else electrical that resets on power cycling (module?).. ...... Does that make sense, Jon et al?

Assuming the pressure switch 5v supply leads are seeing the fuel pump power voltage, what voltage does the PS signal lead send to the ADC point? If it's over 5v, what happens inside the EBL?

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[BruceHislop]

Further to Bill's post,  when troubleshooting intermittent electrical (electronic) equipment first rule of thumb is when it quits, DON'T adjust anything!  If it is safe to do so, observe readings and make some measurements without disturbing the Ignition switch etc.  Once you move a switch or cabling/connectors around you may reconnect an intermittent connection and everything works again.

When I was having issues I noted the "Whirlygig" connection on the top right of the WUD was stopped.  It should spin when the Ignition is ON regardless of whether the engine was running.  So that was my clue that maybe it was losing Ignition power.

Regarding the Fuel Pressure Sensor, if its 5V lead was connected to 12V, there is a good chance its internal electronics is now toast.  The inputs to the ADC should be protected by current limiting resistors and diodes to the 5V power rails so the ADC does not see more than -0.7v to 5.7v which should be within its tolerance.

Bruce Hislop

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[Cameron]

Thanks.   a follow up on a few items.

many of the readings on the WUD continue uninterrupted which is why I called out the few that seemed to change interestingly.  for example, yeah, expect advance to go to zero, but why would the IAT go to -40?  same on the TPS, why would it go to 0 when I am sure I didnt move my foot 'immediately' and if anything I would have thought with the loss of power I would try to give a bit of gas before I realized the engine had died.  

according to WUD IGN doesnt seem to lose voltage, does that mean that I dont have an IGN problem?  is that data in the csv dump?  I dont see a column that looks like that data.

and I agree that I likely did my FPS no benefit by giving it the wrong input voltage and I should likely replace it.

Cameron

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[Bill Van Vlack]

I also found that WUD IGN and FP voltages were not repeated in the datalog. I know their addresses in the WUD serial stream so they could be added to WinLog-EBL and exposed through WinLog's datalog. That would take programming, recompiling, and creating a new driver. An exercise for the dead of winter.

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[Cameron]

hey Jon, was thinking about this suggestion.

do you think that if I used a 'fuse tap' on the fuse for the IGN power and rigg'd a little light to that it would catch if I am loosing IGN power?

(getting prepared for another weekend of troubleshooting...)

thanks!

Cameron

On Wed, Sep 6, 2023 at 8:48 AM Jon Roche <lqqk...@gmail.com> wrote:

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[Jon Roche]

If that is where you power the ign from.  Yes. 

On Sep 11, 2023, at 4:47 PM, Cameron <cbi...@gmail.com> wrote:



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[Bruce Hislop]

Depends on how long your intermittent power loss is. Incandescent lamps are too slow to catch short time intermittents.  Better to use LEDs.

I would connect the LED from a battery source to the Ignition line.  The LED would come ON during the power loss. You would also need a switch in line with the LED because it will light when you turn the key OFF.

I would still put a switch from your Battery to the Ignition. If it starts to act up, flip the switch ON and see if it stops acting up.  It also gives you a backup in case the intermittent power becomes permanent. Remember to flip the switch OFF before turning the Ignition switch OFF else the power from your external switch will feed back and continue to power the engine etc.

Bruce Hislop

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[Cameron]

it is a shame how quickly I get out of my element.

I get in theory what you are saying.  'run a switch so that instead of getting power from the IGN source, it gets direct from battery (taking a possibly faulty ignition out of the loop)'.

unfortunately, my questions are;

1. what kind of switch does this while leaving existing wiring in tack?  regular rocker is load/power/ground.  if I ran BAT to power and IGN to load what does that do to my existing wiring?  would I use another relay (4pin?)?  

2. regarding LED.  definitely like the idea of coming on, as opposed to going off.  way easier to see.  but, again, at a loss on implementation. "connect the LED from a battery source to the Ignition line".  dont even have a guess here on what I would be wiring.

any further detail would be greatly appreciated.

Cameron

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[Bruce Hislop]

I'll type you up more detail when I get home tonight.

Bruce Hislop

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[BruceHislop]

See may answers to your questions below in Blue text.

Hope this helps.

Bruce Hislop

On 11/09/2023 7:05 p.m., Cameron wrote:

it is a shame how quickly I get out of my element.

I get in theory what you are saying.  'run a switch so that instead of getting power from the IGN source, it gets direct from battery (taking a possibly faulty ignition out of the loop)'.

unfortunately, my questions are;

1. what kind of switch does this while leaving existing wiring in tack?  regular rocker is load/power/ground.  if I ran BAT to power and IGN to load what does that do to my existing wiring?  would I use another relay (4pin?)?

You just need a common SPST switch capable of 15 Amps or so.  You just wire it from Chassis Battery power to the ECM Ign power wire.  If it has a light on it, it will come ON whether from the Ignition switch or through this bypass switch.  When the engine quitting issue starts to happen, flip the switch ON and see if your troubles go away.  If they do, you most likely have a faulty Ignition switch or connection block.

The IGN contact in the Ignition switch also powers the Distributor, Gauges, Directional Signals, Backup lights and Cruise Control.  These are handy things to have working if the Ignition switch is failing.  You can use this info to note whether you lose for instance the Directional Signals when you are having engine troubles.

That brings up an interesting question... Does the engine quit when you turn ON the Directional Signals?  If you still have incandescent lamps in the Dir.Signals, they will pull about 5 Amps and increase the chance of a faulty connection failing.

 

2. regarding LED.  definitely like the idea of coming on, as opposed to going off.  way easier to see.  but, again, at a loss on implementation. "connect the LED from a battery source to the Ignition line".  dont even have a guess here on what I would be wiring.

For the LED, just get a little round side marker LED lamp assembly.  The LED wire that is normally Ground is connected to the Ignition wire of the ECM.  The LED wire that is normally Power is wired to the Chassis Battery.  When the Ignition switch is ON, you had 12V on both sides of the LED lamp, therefore zero volts across the LED and it will be OFF.  When there is no power to the Ignition wire, the LED sees 12V on  the battery side and near Zero volts on the ECM IGN wire so it will light up. 

Note: I have not tried this myself, but it should work.  When there is no power to the Ignition wire of the ECM, the LED will find ground through the ECM and other devices mentioned above on the same circuit. You want an LED lamp assembly that does not consume much power, so get a small basic one.  The LED will also Light Up when the Ignition switch is OFF, so you may want to wire a small switch in series with it, but this is just temporary for testing.

[Cameron]

thanks!

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[Cameron]

So, after initially trying to make things way too complicated, I striped a section of the battery wire and striped a section of the ignition wire and wired a SPST switch in between and achieved the desired result.  I was able to start the coach with the ignition wire and then flip the toggle and tested that the engine didnt turn off as expected with the key.

I then moved to a 'road test'.  I left the house, shortly after leaving the coach died (on ignition alone), so having verified the issued still existed I started the engine and switched to battery power.  I drove nicely for 15 to 20 minutes and I started to think we had our culprit.  then it died.  the summary is; it seems to 'die less' with the battery power, but doesnt stop the issue altogether.  Is there a scenario where the ignition is bad AND something else?  or, since it is an intermittent issue was my perceived success just a longer time between failures?  any thoughts on what the something else would be?  (as a refresher I have a new coil and new distributor).

one other thing that I am not sure how it relates - or if it even does.  I do not think I was ever successfully able to start the vehicle, after dying, while on the ignition bypass.  meaning; I am driving along, the engine dies (while on the bypass) and I key off the ignition (which technically does nothing since I am on a bypass) and try to start.  it wont.  but, if I turn off the bypass and try to start, usually starts right up.  then I put the bypass back on.

I will definitely take any criticism of my 'hack' around the ignition or suggestions on other weak points of my installation or testing.

thanks!

Cameron

[Larry Davick]

I suspect an faulty ignition module inside the distributor.  

Larry Davick

1976 Palm Beach

On Oct 2, 2023, at 4:47 PM, Cameron <cbi...@gmail.com> wrote:



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[Bill Van Vlack]

With a SPST switch you are paralleling house and engine batteries when 'ON' and leaving ignition on engine when 'OFF". Are you sure it's not a SPDT switch with three terminals.

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[Cameron]

2 wires only.  I’m sure it is a spst.

I have pulled power by using fuse taps on the main 12v panel behind the glove box.  That should be only engine battery.

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[Cameron]

just in case this one was keeping anybody up at night I thought I would let you know what I believe the resolution was..

I followed the instructions on the ground wire, but I think I had 2 contributing factors to a faulty ground;

1. I dont think it was big enough.  I re ran with a spare cable I found that is probably overkill, but I am going with 'bigger is better' (it is probably 4awg but isnt labeled so I am just guestimating..  similar in size to my battery ground). and I soldered the connections (previous was crimped).

2. the ground that came with the harness had a very small eyelet so I replaced it with a connector with a larger eyelet, but I crimped it.  I pulled that off and soldered another eyelet on.

I am not sure which of the above 'fixed' the ground since both were grounded to the back of the cylinder head but either way, both are 'better' and my problem appears to be solved (3 successful trips)..

I forget who above suggested it was my ground - sorry I didnt listen better!

Happy Thanksgiving,

Cameron

[George Beckman]

You aren’t the only one to not listen to the “check your ground” suggestions.

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