SPI 1991 trouble

[Alex van Zanten]

The SPI 1991 mini of my son has a problem we can't figure out. We made several mems-rosco logs but to us nothing looks off.

The problem we have is increasingly more erratic hick-ups will driving.

Two years ago the car once and again had a hick-up after long runs (over one hour). 

Two weeks ago, the hick-ups already occurred after 30 minutes or so and the longer we drover the more frequent the showed a hick-up. It feels like the car dies and runs again in a very short time. Like a cut-off and no drive. Today my son drove the mini and the hick-up already started after 10 minutes.

The car runs on euro95 e10 combined with the ethanol killer of Miller's Oil.

The car hasn't been driven a lot the past year.

I enclosed a recording of last year as e reference. And a recording of two weeks ago during a long period of hick-ups. 

The hick-ups occur when driving on the high-way and on back-roads. The longer the drive the more often the hick-ups occur when accelerating from stationary of during shifting up.

Sensors seem to work fine, vacuum-lines have been checked.

Any ideas as where to start looking is welcome. 

Best regards, Alex.

[rubenste...@gmail.com]

Hi Alex,

The more I read your email, the more I am inclined to suggest that you renew the crankshaft position sensor with one from a good reputable brand.      These sensors don’t last forever and their breakdown becomes more apparent as the engine gets hot, and that seems to tie in with your symptoms.     An oscilloscope would  be able to prove or disprove it, but in the absence of one, I recommend that you change it.      For the sake of preventive maintenance - rather than run until they break, I have seen recommendations for changing them between 50k miles and 80k miles.          I don’t believe the intermittent hiccup would  show up as a fault code - only an oscilloscope capturing the hiccup would confirm it.

I bought one a few years back from Eurocarparts - I think it was a Bosch sensor - and it didn’t work; on close inspection, there was metal debris on it and one wire has been cut inside the plastic sheath, so do examine the sensor you get for any signs of it having been fitted or returned by someone previously.       A resistance test soon showed me that the sensor was faulty, but that was after I had fitted it.    I don’t intend to make that mistake a second time.

Is the CKP sensor the original one, and has the car done a high mileage?

Martin

[leopold]

Hi Alex,
very strange thing.At first glance i wanted to say "Change your fuelpump" there are solutions with cheap fiat or opel pumps described in the forums.
Then i had a second look to your logfile. If the hick-ups are those negative sparks on the graph, then there is a loss of throttle angle at the same time. But I do not think the throttle poti has gone.I think there is a bad connection between ecu and TPS.Check the wiring and plugs-
When you do next logfile write down the time when the hick-ups occured so we can see on the graph what exactly happened.

[Alex van Zanten]

Thanks Leopold and Martin.
We will start with checking the wiring and connections (after I finish replacing the upper and lower ball-joints on both sides). We will do a test run and when hick-ups still occur, try to record the moments in time.

When the hick-ups still persist, we will replace the CSP sensor with one from Intermotor. And hope for the best.

Best regards, Alex and Bart.

Op donderdag 13 mei 2021 om 09:12:46 UTC+2 schreef leopold:

[rubenste...@gmail.com]

Thanks, Alex.      Please don’t use Intermotor: I think their quality control is dreadful.     I bought an Intermotor rotor arm once and when I opened the box, the brass strip was tilted up by several degrees, so it would have worn and put pressure on the sides of the carbon brush.    I exchanged it and got one that was flat, and this one gave me a very bad misfire even at idle.     I took it back and exchanged it for another, and the same thing happened: the HT was shorting through the rotor arm into the distributor shaft.    Since then, I will never buy Intermotor.

By the way, unlike Leopold, I did not look at the logfile you posted (yet), so Leopold’s diagnosis is likely to be accurate, whilst mine was a guess.   Nevertheless, the CKP sensor is another one of those parts - like an alternator, starter-motor, water-pump, thermostat …. - that I like to replace in preventive maintenance rather than wait till it breaks, usually in bad weather and at night!

But I look forwards to seeing your next logfile and promise to dust off my Windows laptop and look at the file.

[rubenste...@gmail.com]

Alex,

I am perfectly happy with Bosch or NGK/NTK.      But I wouldn’t recommend Intermotor to anyone., although I’m sure there are many who have different opinions.

[Alex van Zanten]

Friday night after finishing the balljojnts the car ran awefull. Again yesterday morning (misfiring/stuttering). The idle switch got stuck. We replaced it last year. Little bit of spray did wonders.

I checked and sprayed all the connectors.

I checked all the fuses at the back of the air filter.

I took out the Cranksaft sensor and cleaned it up and refitted it. The sensor was a bit oily on the outside

Drove for about 30 minutes, no problems sofar.

Today the weather is awefull so no time for a longer drive yet. We hope for better weather tomorrow.

Op vrijdag 14 mei 2021 om 20:13:17 UTC+2 schreef rubenste...@gmail.com:

[Alex van Zanten]

Yesterday the weather was pretty good, so I did a run of about 80 minutes. And no problem what so ever. I guess cleaning the connectors and also fixing the idle switch worked out fine sofar.

During the last 5 minutes the car started to increasingly hesitate on acceleration in second gear. Like you lift off the pedal a little and then accelerate (not flat out), it felt the response was lagging. But than again, is felt pretty hot under the hood.

In don't see any abnormalities in the log. I did enclose the log, for reference. In the start the logging was interrupted shortly. If any off you see anything out of the ordinary, just let us know.

Thanks for all the tips again so far.

Regards,  

Op zondag 16 mei 2021 om 13:42:10 UTC+2 schreef Alex van Zanten:

[rubenste...@gmail.com]

Glad you seem to be making good progress.     I cannot see any attavhed logfile at my end.

[Alex van Zanten]

Mmmm, i am pretty sure i hit the paperclip option and chose a file. I give it another try

Op woensdag 19 mei 2021 om 21:07:58 UTC+2 schreef rubenste...@gmail.com:

[rubenste...@gmail.com]

I’ve looked at your logfile using mems-rosco.     Unfortunately, because of differences in formatting between the software packages, the logfile doesn’t open with MEMSAnalyser.     On a first look, I cannot see anything out of the ordinary.     It is going into open loop when you accelerate hard, as it should, and is dropping back into closed loop shortly afterwards, again, as it should.      Your LTFT at 130 does not give any cause for alarm, and your STFT stays close to 100, as it should be.  (Because of the low sampling rates, it isn’t possibly to get an accurate measure of the switching rate/frequency of the lambda sensor, so it isn’t possible to say if it has gone a little tired with age - you’d need a ‘scope for that.   But the lambda sensor appears to be working perfectly)      But everything I’ve seen makes me think your car is running well.     I’d be interested to read what others think.

[Andrew Jackson]

Martin I can convert the file and replay it through memsfcr. Will take a look.

[leopold]

Hi Andrew
 I wanted to test your newest versions of memsfcr and memscene  to see how alexvZ  logfile looks like in your software.But i can not open it.
This is the rror message.

Can you give us  a manual or hint what to do!
Leopold

[Andrew Jackson]

Hi Leopold,

My bad here, I created the memscene to help me convert files and it was an afterthought to share it - as such I didn't supplied any help. I'll put a page on the website.

The app attempts to auto-detect the source format and creates a memsfcr version.
Essentially MemsFCR uses the timestamp, raw 7d and raw 80 fields only so the app reverse engineers the formatted data back into raw data.
If it can't detect your file or you get exceptions let me know and I can fix or add relevant support.

The command line is as follows:

memscene -file <path to source file> -output <output filename>

-output is optional, file will be created in current directory as <source filename>.output.csv

The dot slash is required on the command line in MacOS and Windows as shown in your screenshot e.g. ".\memscene.exe" on Windows or "./memscene" on Mac

Andrew

[Alex van Zanten]

Back again and still in trouble. But I think we now have a better log.

So I checked and cleaned up all the connectors and after that ran the car without any problems for 75 minutes.

When my son drove the car the the APK/MOT/TuV check, the hick-ups came back.

So finally we replaced the flywheel sensor. At the same time I re positioned the rear part of the exhaust.

My son took the car to work (30 minutes drive on-way), no problems to and from work.

When i re positioned the exhaust, I noticed the oil seal of the shifter shaft had come loose. 

I drove the car to my parts supplier (about 35 minutes). I noticed a slight hesitation when accelerating on the motorway.

On my way back, the hick-ups started coming back again.

Very recently the car also suffers from vibrations between 90 en 105 kmph. Furthermore a ticking (clicking?) sound could be heard coming from the front rightside of the car. 

My parts supplier suggested a faulty inner CV joint as possible cause.

So I replaced both(!) CV inner pot joints with brand new ones. That didn't solve the problem one bit (stiil working on that problem).

Also intended to replace the fuel filter, but unfortunately the wrong version was supplied to me. So I refitted the existing one. 

Afterwards the car ran even worse (luckily!). Started hesitating with every accleration, when driving about 60 kmph in third or fourth gear. Sluggish acceleration throughout the revs. Terrible. Budging when driving at even speed. It feels like no fuel is injected? 

At the moment the acceleration is poor in all gears after the car is warmed up a little.

Why luckily? This gave the opportunity to record logging which should contain plenty of info where the problem might lie.

I use MEMS-Scan 0.5.2 for recording the logfile.

I use mems-rosco-logs-charts 2.2.2 examining the logfile 

Within MEMS-scan some errors are reported under the Errors tab. Number 17 and 18 with unknown category.

But also under Anomalies: Unusual low lambda signal. But I have no clue what the lowest value is usual. 

After I parked the car and stopped the recording suddenly number 20 Lambda heater supply voltage lit up as error.

When looking at the log, the absence of fuel is confirmed several times when I look at the airfuelratio. But that is the consequence when you accelerate, only it takes to long for the mems starts injecting the neede fuel.

Could we suffer from a faulty lambda sensor? 

I hope you can help us out. And can pinpoint any abnormalities in the log.

The log from 2021-07-09_08:00 = to work is one of the no problems run.

The log from 2021-08-08_14:25  = the one with car performing very poorly.

Regards, Alex.

Op maandag 24 mei 2021 om 11:18:54 UTC+2 schreef andrew.d...@gmail.com:

[rubenste...@gmail.com]

Alex

Sorry to hear that you are still having problems.

I have attached 3 pictures - I wish I could insert them into the text, (and I wish we could edit our posts after sending them as well).   

 I attach the 3 screenshots to illustrate something that I need advice on from people like Leopold.        I looked at your lambda voltage using Leopold's mems-rosco - sadly, the logfile won't open in MemsAnalyser - and this is where I need advice: when I look at a two-minute section (see attachment beginning with Alex 2 min), there appears to be very little switching.      Compare that with a two-minute section from my car using an oscilloscope (see attachment  2min on PicoScope).        My lambda sensor is switching 2 or 3 times a second, as it should.         Yours APPEARS to be switching very, very much less.    However, we know that the sampling rate on the logfiles is too low to get an accurate picture of the lambda voltage, but what I need advice on is: does yours look normal taking account of the aliasing caused by low sample rate, or is your lambda sensor not switching enough, possibly because of a heater fault or some other reason?

When I look at lambda voltage, I only use my 'scope  because of the problems with low sample rates on logfiles, and, when I do make a logfile, I use Al Richey's memslogger and then use MemsAnalyser, and that's where the third screenshot comes in: I have taken a two-minute section from one of Al's demo files and shown it in MemsAnalyser, and it again questions whether your lambda sensor is switching frequently enough or whether we are simply looking at an anomaly caused by too low a sample rate.    So that's why I'm hoping Leopold will look at your lambda voltage and will tell me if it looks normal  (as a logfile display).

Sorry I can't be more helpful, but as a first step I think we need to know if your lambda sensor is good or bad, and. at the moment, I cannot be sure.

Martin

[rubenste...@gmail.com]

Alex,

You used the phrase, “ the hick-ups came back“ and “Terrible. Budging when driving at even speed”

Can I clarify what you mean?        To me, a “hick-up” is a definite, noticeable event, like a sudden jolt.    I have had ignition faults where, when you try to accelerate, there is quite a violent jolt to the car as it fails to respond.    On the other hand, when I have had fuel starvation and pressed the accelerator down, there is a smooth slowing down, not violent, and I can even hear the sound of air being sucked in with nothing else happening other than the engine losing rpm.        And what do you mean by “terrible budging¨?        So does your problem feel more like the harsh, even violent, reaction you get with an ignition misfire, or is it more like the smooth loss of power when you have sudden fuel starvation?

Attached are 2 photos of what I use to test the fuel pressure after the filter (unless I use a pressure transducer and a ‘scope).    The gauges I got on ebay along with the T-piece and connectors.      My fuel pump is supposed to pump at 1 bar.     There is a possible problem: you can really only test with the car stationary - you cannot easily drive at speed and watch the gauge when you accelerate.     But you can at least test it at idle and when revving the engine.       

Martin

[Andrew Jackson]

Alex,

If you have a PC remove the first line of your logfile and rename the file from xxxxx.TXT to xxxxx.CSV.

You will be able to open the files in Excel or Google Sheets and create a graph of the Lambda voltages.

The voltage oscillation looks ok to me, if the lambda sensor isn't working properly it would be easy to spot.

My hunch is this is a fuelling or ignition issue given the hesitations you get. Martin and Leopold are better qualified than me on this subject.

Andrew

[Alex van Zanten]

Oops, i replied last week but used e-mail. Missed the error message.

@Andrew: i agreed  on the fuelling problem. It was caused by my quick refitting of the old fuel filter. The small flex  hose got a wrong bent, so fuelsupply was limited. Corrected that issue when i fitted the correct filter. No fuelling troubles anymore.

Last winter we fitted sound isolation under the hood. We used the old looking stuff. Because the troubles increased afterwards, we now removed the sound isolation. Hoping the hood helps to radiate heat out of the engine bay.

I drove the mini Saturday for two test drives. The only thing i noticed was hesitation when shifting up in second gear. When shifting up and accelerating the car hesitates and accelarates. Shifting up to third and fourth gear no propblems. When you accelarate carefully in second gear, the hesitation is not noticible.  

Bart took the car on Monday to work, only a few hesitations in second gear and he was carefull when accelarating. And no jolts.

Bart took the car again yesterday and pretty soon the sharp hick-ups returned. And kept ginving jolts to and from his work. We didn’t do anything to the car, it just had been sitting on our driveway.

@Martin what we experience is a sharp sudden short jolt when driving at constant speeds. At all kind of speeds and in all gears. The number of jolts increase over time.

When thinking back two years ago, this problem presented it to me the first time. After selling our family car, i used the mini when visiting some  cardealers on the same day. First drive of 60 minutes no problems. Second drive of 75 minutes, an occasional jolt occurred after 45 minutes. About 3 times. The third drive of 60 minutes, after 30 minutes several jolts, but only on the motorway. 

Next day two drives of 75 minutes. First drive one jolt, second drive about 3 or 4 jolts after 45 minutes.

Two weeks later two drives of 60 minutes. First drive one jolt after 45 minutes, second drive about the same.

After that, the car has only been driven for runs of about 30 minutes by Bart. And due to COVID hardly for a year.

Up untill now, my assumption was, the jolt is heat related. But now i am not so sure anymore. Over the past 4 years some sensors have been replaced. Lambda, Air temperature, heater PTC inlet manifold, the sensor for the second fan, water temp sensor, recently the CPS sensor. Rotor, Rotor cap and ignition leads have been replace again. I renewed the ignition coil (Intermotor) , made sure i used the electronic ignition type coil. Replaced the fuel filter. I had to replace the throttle potentiometer for a spare (used) one because the fitted one was broken. That’s when i got myself a second hand laptop and started using the mems rosco software.

I replaced the throttle switch for a brand new original one. All new vacuum lines all around.

The logging doesn’t provide any clear errors. It feels like i am running out of options to solve this issue by myself.

Best regards,

Bart and Alex.

Op maandag 9 augustus 2021 om 11:20:26 UTC+2 schreef andrew.d...@gmail.com:

[leopold....@t-online.de]

replace fuelpump too.There are cheap ones for opel or fiat on the aftermarket.They should have between 1,5 and 3 bar.

[rubenste...@gmail.com]

Alex,

A “jolt” is a good description - there’s no mistaking now in what you experience.      I know you’ve replaced all the ignition parts - or practically all - but the jolt you are describing makes me certain it is an ignition misfire.        If you had access to an oscilloscope and HT lead pickups, you could drive it and I feel certain you would see it.     And the jolt occurs under acceleration load, which is where you would expect it.     A fuel-starvation misfire, would be much gentler - not a jolt.      I had this only once on my car, I went to accelerate hard in second gear to overtake on a very wet day and the car jolted violently 3 or 4 times, so I stopped accelerating - too dangerous!

I have told you I once fitted 2 new Intermotor rotor arms and both gave misfires even on idle.     But even an oscilloscope confirming that you have an ignition misfire won’t tell you where the problem is.     Did you say you renewed the spark plugs?    You could have a hairline crack in one of them.   ( I fitted some iridium ones to my car, but do be sure they are the correct ones and a known reputable make.)

If yours is an Intermotor rotor arm, I would certainly replace that with a different, but reputable make before doing anything else.

Does this happen when the components are cold, or is it worse when everything is hot?        Breakdown of electrical insulation is worse when hot, generally, but I’m sure you know that already.

Martin

[rubenste...@gmail.com]

Sorry Alex, when I wrote “   I had this only once on my car, I went to accelerate hard in second gear to overtake”, I meant I had ignition-breakdown jolts only once (and not a lean-mixture/fuel-starvation lack of power).     There’s no mistaking it: it’s quite a jolt.

[Alex van Zanten]

@leopold: i don't understand how replacing the fuelpump will fix the problem. Apart from the labour,  i don't believe our problem is fuel related. 

@martin Will check plugs when the new coil arrives wednesday. Early 2019 i replaced a lucas sports coil for an intermotor 11410 dry coil. Now i ordered the NGK U1076. Early 2019 i also replaced all leads,  rotor arm and distributer cap with items supplied by moss motors. All of them  are not Intermotor. 

Will if this brings any change for the better. 

Regards, Alex.

Op donderdag 19 augustus 2021 om 13:10:34 UTC+2 schreef rubenste...@gmail.com:

[rubenste...@gmail.com]

Alex,

Do you still have that that Lucas Sports coil?     And did you experience the jolting with that coil?       If you know that that coil is a known good coil, then you could swap the current coil over now, changing nothing else at the same time, and see if the fault is still there.    You could then either rule out the existing coil or prove it guilty.

Similarly, when you do come to replace existing parts, it would be good if you would change only one thing at a time: if you change everything, - and the car is fixed - you won’t know where the fault lay, and which of the old parts can be trusted as spares.

(And you could also give some thought to what would you do if you change all the parts and the fault is still there; what would you change/check then.)

[Alex van Zanten]

I had the same thought on the lucas sports coil. But when i got out of the box with spare mini parts, fluid came out of the top. When i shake it, i here fluid splashing around. That is why i opted for the NGK one this time. Will keep in mind to change one part at a time.

Op zondag 22 augustus 2021 om 20:55:24 UTC+2 schreef rubenste...@gmail.com:

[Alex van Zanten]

OK, so i replaced the coil, still in trouble. 

Before replacing the car drove the car for about 15 minutes. Replaced the coil, drove the car again, no difference what so ever.

Next I choose to fully reset the ECU using mems-scan.

Started the car and had it running a few minutes.

Was called in for diner and after diner took the car for a drive.

It is about 8 minutes to get to the motorway, then i drive to the next exit (about 4 minutes) and drive back again to our own exit and again another 8 minutes to get home.

It feels now the jolting has changed into a bog-down before accelerating when shifting up and giving a fair bit of throttle.

First small one after 7 minutes, second after 8 minutes. During the first motorway run slight hesitations accelerating. When you drive at a constant speed short hesitations can be felt. It has moved a way from jolts.

On the return part of the motorway run the hesitations got worse.

In the 8 minutes back to the house, accelerating in any gear resulted in a bog-down before accelerating. In the last 2 minutes i heavily gave throttle in second gear, and every time the car bogs-down strongly before accelerating.

Perhaps Leopold is right about the fuel pump getting worse, resulting in insufficient fuel pressure?

I enclose the log of tonight. I don't know which measurements i must few together to pinpoint any problem area.

I use mems-rosco-logs-charts 2.2.2 to read the log file.

Regards, Alex. 

   

Op zondag 22 augustus 2021 om 21:24:13 UTC+2 schreef Alex van Zanten:

[rubenste...@gmail.com]

Hi Alex

You say no difference whatsoever, but you also say “it feels now the jolting has changed into a bog-down before accelerating”.

Did you experience ANY jolting at all?      Is it possible your new coil fixed a high-tension ignition breakdown fault, and, having fixed that, it has now made the additional fault of fuel starvation is all the more apparent?   Is that a possibility - that you have had 2 separate faults?

Didn’t you say there was some sort of problem with the fuel filter,  and, as a result, Leopold advised you to fit a new fuel filter?      (Was the car stood for a long time and the gel from the separation of alcohol and petrol in E5 petrol, when left for a long time, partially blocked the filter?).   Did you fit a new fuel filter?

[Alex van Zanten]

Martin,

you are right, something has changed. What i meant was, after switching the coil still problems occur.

I replaced the fuel filter two weeks ago and fixed the pinched fuel line coming out of the filter. I also replaced that short piece of flex fuel line.

After that the car ran fine for one day. And two days later problems were reported by my son. Unfortunately my son isn't clear in pinpointing out the problems. I thought the jolts were still there. But yesterday it all about hesitation when accelerating.  I will check the vacuum lines again. All the sensors seem to work nicely. The flex fuel line used is a Gates Multi carburant 3225 8mm GL08/21/04. Could this cause a flow problem, not sure if it is suited for ethanol fuel (we do use a ethanol killer). The old fuel line looked fine on the inside.

I don't understand why the car drove fine the first day and poorly two days later. The car was completely untouched.

I am starting to get frustrated unable to determine the source of the problem.  

@leopold: Regarding the fuel pumt you stated: There are cheap ones for opel or fiat on the aftermarket.They should have between 1,5 and 3 bar.

Don't know much about alternative fuel pumps, but as it is a SPI,  is 1,5 bar and up not to much fuel pressure? I always read fuel pressure should be just over 1 bar for a SPI.

And could you point me partnumbers of the alternatives you mention?

The cheapest solution i can find over here is https://www.classicminionderdelen.nl/webshop/motordelen/-brandstofsyteem/detail/967/benzinepomp-spi-mpi.html 

Any suggestions what to try out next or check regarding the current bogging down is still appreciated.

Thank you so much for your time and patience.

Best regards, Alex. 

Op woensdag 25 augustus 2021 om 20:59:40 UTC+2 schreef rubenste...@gmail.com:

[Alex van Zanten]

Saw the answers in the email (but not over here?). We are on holiday for the next two weeks. Will pickup fixing the problem after we return (hopefully less frustrated).

Op donderdag 26 augustus 2021 om 13:52:02 UTC+2 schreef Alex van Zanten:

[Mark Ashworth]

I used to get this type of jolting when I had a bad cam sensor on my t series turbo.

[Mark Ashworth]

It was a long time ago. However as far as I can remember it was when accelerating past a certain point.

Took me a while to suss it, but it turned out the cam sensor only had any affect on the timing of the fuelling up to 3500 rpm which is where the ECU switched from sequential to batch fuelling.

It was around this point the jolt happened.

May not be related to your issue, but something to look at?

[rubenste...@gmail.com]

Thanks, Mark.        Interesting: I never realised that the fuelling regime might change with RPM.      With your fault linked to your camshaft position sensor, I wonder if that implies that MEMS gets its RPM data from that sensor rather than from the crankshaft position sensor (on engines with a cam sensor).

And I’ve just noticed it says SPi in the title.     My K series engine is also SPi, and it doesn’t have a camshaft position sensor.      Do you know if camshaft position sensors were fitted to SPi engines, or were they restricted to MPi engines only?

[Mark Ashworth]

Regarding SPI's, you know I'm not so sure without consulting the workshop cd.

The rpm is still derived from the crank sensor, however, the engine will run perfectly fine if either the camshaft sensor or the crankshaft sensor fails.

Like I say camshaft sensor signal is for sequential fuelling only. I guess if the camshaft sensor fails it batch fuels even at low rpm.
Plus I just remembered, another symptom of the cam sensor failing was a delay in starting. It would take a few seconds if turning the key before starting. It seems the ECU realises no cam sensor input and switches to the crank sensor for fuelling.

[Alex van Zanten]

The holiday feels like months ago. So after we returned i replaced the fuelpump using a kit from my supplier. To be save i opted for the MPI fuel pump, pressure enough and the pump self regulates. Acceleration problems are solved and sofar no sudden jolts anymore when driving the car between 30 and 45 minutes.

It's a pity the new fuelpump is more noisy, but that will be discussed with my supplier. Next we ar going to focus on the vibrations in the front suspension. Figuring out what is the cause.

Thank you so much for your patience and all the good suggestions. 
@leopold: your first suggestion was the solution to this problems (replace the fuel pump).

Best regards: Alex and Bart  

Op donderdag 26 augustus 2021 om 17:31:00 UTC+2 schreef Alex van Zanten:

[rubenste...@gmail.com]

Many thanks for the feedback, Alex, and especially for telling us that your car is now fixed and how you fixed it.

A couple of questions for you:

1.     Was the original fuel pump inside the tank, and did you have to remove the tank to fit the new pump, or is the new pump external to the tank and it draws the fuel through the old pump?

2.    Can you give me an Internet link to the MPi pump kit you used, please?

3.    What made you decide to replace the fuel pump?    Did you measure the output pressure and it was low, or perhaps you replaced it because you had checked everything else?

The Pico NVH kit and oscilloscope would quickly help you locate the source of the suspension vibration, but it’s unlikely you’ll know anyone locally who has such a kit.      On the other hand, if you leave the vibration alone, the fuel pump won’t sound so noisy😁.      I shouldn’t encourage you to go off this topic, but what are the symptoms of the vibration?

Matin

[rubenste...@gmail.com]

Alex

One other thing: it looks like your long term fuel trim was 137, so that is +12, indicating MEMS needed to increase the fuelling, but I don’t know if +12 is abnormal - it’s a long way off +20, which would send it into open loop.    (Mine is currently -7.)

I’d be really interested to know your new LTFT with the replacement pump.      I expect it will come down and perhaps even go negative, but it would be very helpful to know if we could use a +12 LTFT, in the future, as an indicator.

Martin

[rubenste...@gmail.com]

Correction: it’s 128 not 125, so your old LTFT was +9 (not +12).    (Mine is still -7 ie 121.).    

Very interested to know what the new LTFT is.