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

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

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

Hi James,
Your computer has been thrown into the limp mode. Probably by one
of the disconnected vacuum hoses that controls one of the sensors.
God Bless America, ßill O|||||||O
mailto:-------------------- http://www.----------.com/

James Morrow wrote:
>
> 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

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

Hi James,
Your computer has been thrown into the limp mode. Probably by one
of the disconnected vacuum hoses that controls one of the sensors.
God Bless America, ßill O|||||||O
mailto:-------------------- http://www.----------.com/

James Morrow wrote:
>
> 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

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

In article <5bb7cfd4.0309012219.1d2c2ce4@posting.google.com >,
jmorrow@elitecarstereo.net (James Morrow) wrote:

>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

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.

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

In article <5bb7cfd4.0309012219.1d2c2ce4@posting.google.com >,
jmorrow@elitecarstereo.net (James Morrow) wrote:

>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

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.

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

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

James Morrow wrote:
>
> 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

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

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

James Morrow wrote:
>
> 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

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

Yep, me too! Take the converter off temporarily.

----

On Tue, 02 Sep 2003 09:48:14 GMT, "Wildman" <mjswildman@excite.com>
wrote:

>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.

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

Yep, me too! Take the converter off temporarily.

----

On Tue, 02 Sep 2003 09:48:14 GMT, "Wildman" <mjswildman@excite.com>
wrote:

>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.

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

"James Morrow" <jmorrow@elitecarstereo.net> wrote in message
news:5bb7cfd4.0309012219.1d2c2ce4@posting.google.c om...
> 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