Help! Jeep Cherokee can't go over 20mph!!!

[James Morrow]

Hey everyone! I need some help. Ok, the long and short of it is that
my 88 Jeep Cherokee Pioneer won't go over 20mph. It has the 4.0 L6 and
it's an automatic.

Now, 3 days ago it was fine. Everything ran great. Then, I decided
that I wanted a better air intake system, so I disconnected the filter
housing from the intake arm and stuck a cone filter on the end of the
arm. I relocated the CCV hoses to the intake arm, but nothing else. At
first it seemed to give a noticable power gain and much more
aggressive tone. Then, over the next three days, it has been gradually
slowing down. The engine will still rev just as hard as ever, but I
can be in 4th gear on a straightaway at 5k/rpm and I'll only be going
25 or 30mph. Now, I thought that I might have messed somehthing up
when I modified the intake system, so, I took off the cone filter and
put the stock housing back in. No such luck! However, during the
intake modification I lost the caps off of a couple of the vaccum
hoses (2 that run to the back of the air cleaner housing & other misc)
so they are not currently hooked up. Everyone I know says that they're
not sure what the problem is but that disconnected vaccum hoses would
not cause any problems of the sort. Several also say that the timing
is just a coincidence and that the air intake system would have
nothing to do with my problem. They say it sounds like a tranny issue.
Do you think maybe I messed up a sensor and the computer's ratios are
messed up? Has anyone ever heard of a problem like this happening
before? I tried searching the internet but I couldn't find anything
related to my problem mainly because I have no clue what is causing
it. If anyone has any insight as to what is wrong with my Jeep I would
really appreciate the help. It's my baby and I just wanna get it
runnnin right again asap. Thanks!

James Morrow

[Joseph Oberlander]

James Morrow wrote:

> nothing to do with my problem. They say it sounds like a tranny issue.

Yep. Tranny. It is likely unrelated. Mine just went out last time
with about 3 blocks warning. Fine fine fine fine - dead as a rock.
Well, it did run - but maybe 20mph in 1st gear. For a few days, then
it gave out as well. In your case, it may be that you got jammed in
4-Low. Of course a new transfer case or transmission? $$$$.

15 years old? Yeah - probably time for it to die the second time.

My recommedation - time to look into getting a new vehicle.

[Bill Kapaun]

In article <5bb7cfd4.03090...@posting.google.com>,
jmo...@elitecarstereo.net (James Morrow) wrote:

I don't know if your transmission has a vacuum modulator or not, but if it
does AND it's not getting vacuum, it won't upshift.
It senses engine load by the amount of vacuum (low vacuum, heavy
load--high vacuum, light load). It "thinks" the engine is lugged down.

[Wildman]

Make sure your catalytic converter is not plugged. My 93 XJ had the same
problem. I thought it was a tranny issue, but it boiled down to a plugged
converter.
"James Morrow" <jmo...@elitecarstereo.net> wrote in message
news:5bb7cfd4.03090...@posting.google.com...

[Mike Romain]

You have a mechanical kick down at the throttle body and a TPS that
controls the shifting.

I would be suspecting one of those first.

Even with vacuum leaks it should shift. Vacuum leaks aren't a good
thing though. I use a chunk of hose with a bolt in it for a cap if I
have misplaced the rubber ones.

Mike
86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
88 Cherokee 235 BFG AT's

[Chris Z.]

"James Morrow" <jmo...@elitecarstereo.net> wrote in message
news:5bb7cfd4.03090...@posting.google.com...

> aggressive tone. Then, over the next three days, it has been gradually
> slowing down. The engine will still rev just as hard as ever, but I
> can be in 4th gear on a straightaway at 5k/rpm and I'll only be going
> 25 or 30mph. Now, I thought that I might have messed somehthing up

Did you bother to check the transmission fluid level when this started to
happen? If not, and it's low enough to cause this much slipping, I'd guess
there's a good chance you killed the tranny by continuing to drive it this
way.

Chris

[Daniel J. Stern]

On 1 Sep 2003, James Morrow wrote:

> Now, 3 days ago it was fine. Everything ran great. Then, I decided
> that I wanted a better air intake system, so I disconnected the filter
> housing from the intake arm and stuck a cone filter on the end of the
> arm.

This is not "better" in any way, shape or form.

> I relocated the CCV hoses to the intake arm, but nothing else. At
> first it seemed to give a noticable power gain and much more
> aggressive tone.

The power gain was your imagination (or your having replaced a dirty stock
filter with a clean cone), aided and abetted by your ears hearing the
intake roar.

> Then, over the next three days, it has been gradually slowing down. The
> engine will still rev just as hard as ever, but I can be in 4th gear on
> a straightaway at 5k/rpm and I'll only be going 25 or 30mph.

Sounds like bigtime transmission slippage. Checked your transmission
fluid...lately? Do so now. What's it smell like?

> during the intake modification I lost the caps off of a couple of the
> vaccum hoses (2 that run to the back of the air cleaner housing & other
> misc) so they are not currently hooked up.

Probably not causing your problem, but also not something to just shrug
and say "Whatever..." about. Those hoses are there for a reason. Fix 'em!

> Do you think maybe I messed up a sensor and the computer's ratios are
> messed up?

The computer has no ratios.

DS

[Brandy Wood]

Try the catalic converter, or the bands on the tranny are slipping. try
Jose martinez outta trumbell tx, heres the number 972-544-3267 he's the
cheapest out there with a greatest warranty.
bw

"James Morrow" <jmo...@elitecarstereo.net> wrote in message
news:5bb7cfd4.03090...@posting.google.com...

[Dan Lefrancois]

: Hey everyone! I need some help. Ok, the long and short of it is that

: my 88 Jeep Cherokee Pioneer won't go over 20mph. It has the 4.0 L6 and
: it's an automatic.

: Now, 3 days ago it was fine. Everything ran great. Then, I decided
: that I wanted a better air intake system, so I disconnected the filter

I had a very very similar problem (although not caused by any mechanical
changes). I thought my tranny was a goner. Turns out it was the TPS
sensor. Simple to fix. I'd recommend you try this first, before looking at
the tranny.

Dan

[Clem]

4th gear and 5k rpm and 20 mph?

You have serious tranny problems.

"James Morrow" <jmo...@elitecarstereo.net> wrote in message
news:5bb7cfd4.03090...@posting.google.com...

[Clem]

'88 was still amc.. too bad.

If it was chrysler you could scan the computer very easily for codes, which
would tell you whether it's the TPS or not.

AMC is probably scannable... check out www.batauto.com and find the trouble
code section.

"Dan Lefrancois" <lefr...@interchange.ubc.ca> wrote in message
news:bj43sg$15f$1...@nntp.itservices.ubc.ca...

[Kevin in San Diego]

No the 88 isnt really scannable. I dont think you can even find a daignostic
tool for the port on that thing.
KH

"Clem" <mygodistherea...@yahoo.com> wrote in message
news:vlfamrr...@corp.supernews.com...

[Dave]

Yes Bendix made testers that the Jeep dealers used to hook up to the 88 XJs.
Snap on also makes adapters that will work too.
later,
dave (with the Bendix)
88 XJ

"Kevin in San Diego" <kevin_h...@yahoo.com> wrote in message
news:XjT5b.44538$Qy4.42417@fed1read05...

[Mike Romain]

My book says a DRB 11 tool can read the 88's. The V6's had a self
diagnostics and 91 to 97 have them.

Mike
86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
88 Cherokee 235 BFG AT's

[greg pabst]

I also had the same symptoms, and also thought it was a transmission problem,
and it turned out to be the catalytic converter

[Kevin in San Diego]

Where can I get my hands on one of those temporarily I wonder?
KH

"Mike Romain" <rom...@sympatico.ca> wrote in message
news:3F588EC6...@sympatico.ca...

[BB]

Some auto parts stores have them for 'rent', some don't even charge anything
for it, just a deposit untill you return it. Check with the more common
stores, ie: autozone, checker, etc.
BB

"Kevin in San Diego" <kevin_h...@yahoo.com> wrote in message

news:jE66b.45776$Qy4.29312@fed1read05...

[Kevin in San Diego]

Yea, no one seems to have one.
KH

"BB" <bru...@computerxmedics.cc> wrote in message
news:3KCcncunWIl...@comcast.com...

[Steve m...]

Those engine diagnostics monitors were rare due to it's AMC design. I
would imagine even now anywhere short of a dealer will be tough to locate
one to "borrow".

Steve m..

"Kevin in San Diego" <kevin_h...@yahoo.com> wrote in message

news:bxO6b.47273$Qy4.23187@fed1read05...

[Kevin in San Diego]

I guess I could ask my dealer.
KH

"Steve m..." <Steve...@bigfoot.com> wrote in message
news:vlnfqgn...@corp.supernews.com...

[Don]

Jim - Sounds like your tranny - are you sure you didn't accidentally
disconnect some vacuum hose leading to the tranny during your work? You may
want to put everything back to stock and see if the problem goes away. (If
you covered this, I apologize - at my age, don't have the time to read the
whole story). Maybe, your new cone filter drops the vacuum so much (much
more free flow) that it confuses the tranny or the electronicals (heh, that
is what us old timers call them) that it does not know what gear to put the
tranny in. Can't remember - yeah I know it's old age so don't tell me -
when did Chrysler buy Jeep? - is it an electronically controlled Chrysler
tranny or one of the old Jeep trannies? If Chrysler, I'd be more suspicious
of the thinking that it is trying to do.

Good luck,
Papa Don

"James Morrow" <jmo...@elitecarstereo.net> wrote in message
news:5bb7cfd4.03090...@posting.google.com...

[Kevin in San Diego]

Maybe a shift solenoid is bad or not getting voltage, when my compushift is
on, it revs without moving much.
This was alink Bill posted a while back.

http://www.transonline.com/transdigest/magazines/1997-10/Shift%20Pointers/index.html

KH

"Don" <N...@This.Address> wrote in message
news:VXQ7b.24730$n94.5720@fed1read04...

[ali bin ali]

i can help u by telling u some information about ur car,, because
acttuly i have a wrangler,, it's same engin and same gear box but ur
problem is that u car dosn't go over 20mph,, so u have a problem with
the computer system u have to chaeck it,, or u can buy a cheap for ur
car and that cheap can allowd u to go over 240k/m

[TJim]

Huh?

--
Jim
98 TJ SE
90 SJ GW
http://www.delawareja.com/gallery/JDJeep98

"ali bin ali" <bu_fai...@hotmail.com> wrote in message
news:df839a94.03091...@posting.google.com...

[Dave Milne]

He says the computer is knackered, and if you should either check it,
or leave it knackered and chip it, which will give you a top speed of over
150 mph.

I now understand why Americans can pronounce sh*t with 4 syllables.

Dave Milne, Scotland
'99 TJ 4.0 Sahara

"TJim" <j...@ranlet.nospam.com> wrote in message
news:UISdnR9QJq9...@comcast.com...
: Huh?

:
: