Please help with diagnosis...
 

Hi, I've got a bit of a problem with my 98 TJ 4.0l 5 speed.

Here's what happens...

Around town, all is fine, but once I get on the highway for a while at
consitantly higher rpms...around 2200 or so..at 65mph in 5th, it will randomly,
and without notice suddenly start to sputter, does a small backfire, and the
rpms drop immediatley. Adding gas does nothing but drop the rpms faster, and
all I can do is pull off the road before being forced to a stop in the middle of
the highway. It doesn't die, but will just sputter away at just under regular
idle speed. I have found that I can shut it off, and let it sit for a minute,
then restart..(no problems restarting), and I can sometimes continue for a
while, sometimes just a few hundred yards before it does it again. If I can
get to an exit, I can drive it all day around town with no problems.

Here's what i've done so far...

I changed the plugs, wires and distributor cap...no effect

It did it once on the way to a job appointment, so I had to limp it to the
nearest dealer, and got a quick rental while they took a look at it.
They of course could not duplicate the problem, but they ran a minimum air flow
test and it failed that, so they did an induction service, emisions flush, and
clenaed the throttle bore and induction system of carbon deposits.
$125...I was glad to get out of the dealer with a bill that low..lol, and I
hoped that just maybe, that was the problem. Yep, you guessed it...no effect!

Has anyone experienced this type of thing before, and can advise me furthur?

Any help is appreciated.

Regards, Kelly

Re: Please help with diagnosis...
 

"Kelly J" <Kelly_member@newsguy.com> wrote in message
news:bgk97a0tmu@drn.newsguy.com...
> Has anyone experienced this type of thing before, and can advise me
furthur?

hi kelly,
my money says your catalytic converter is clogged.


--
Nathan W. Collier
http://7SlotGrille.com

Re: Please help with diagnosis...
 

also..........might could be fuel pump........

--
Carlo F. Serusa, Jr. RPh
carlo.jr@comcast.net
'98 Sahara TJ - '89 YJ - '79 Scout II
O|||||||O
'92 Explorer '65 Mustang


"Carlo Jr." <carlo.jr@comcast.net> wrote in message
news:KgiXa.41875$cF.15557@rwcrnsc53...
> Ditto...........or maybe how about the fuel filter (high speed problem) ?
>
> --
> Carlo F. Serusa, Jr. RPh
> carlo.jr@comcast.net
> '98 Sahara TJ - '89 YJ - '79 Scout II
> O|||||||O
> '92 Explorer '65 Mustang
>
>
> "Nathan W. Collier" <abuse@A0L.com> wrote in message
> news:19iXa.381744$jp.10893415@twister.southeast.rr .com...
> > "Kelly J" <Kelly_member@newsguy.com> wrote in message
> > news:bgk97a0tmu@drn.newsguy.com...
> > > Has anyone experienced this type of thing before, and can advise me
> > furthur?
> >
> > hi kelly,
> > my money says your catalytic converter is clogged.
> >
> >
> > --
> > Nathan W. Collier
> > http://7SlotGrille.com
> >
> >
>
>

Re: Please help with diagnosis...
 

In article <bgk97a0tmu@drn.newsguy.com>,
Kelly J <Kelly_member@newsguy.com> wrote:
>Hi, I've got a bit of a problem with my 98 TJ 4.0l 5 speed.

There are many responses from CAT to fuel pump. You have a 1998 and
I can't see the CAT being bad and if it was the fuel pump, you wouldn't
be able to drive around town or anywhere.

I think you have blow-by into your intake. Have you checked your air
filter lately? You will probably need to clean or replace your CCV and
the hoses. The intake hose to the valve cover too. You should also
inspect your ribbed intake hose going from your air filter cover to
your throttle body for cracks or looseness. Also check your MAP sensor
module with a vacuum pump to see if it's holding vacuum.

You did okay with the electrical, now try the intake side.

>
>Here's what happens...
>
>Around town, all is fine, but once I get on the highway for a while at
>consitantly higher rpms...around 2200 or so..at 65mph in 5th, it will randomly,
>and without notice suddenly start to sputter, does a small backfire, and the
>rpms drop immediatley. Adding gas does nothing but drop the rpms faster, and
>all I can do is pull off the road before being forced to a stop in the middle of
>the highway. It doesn't die, but will just sputter away at just under regular
>idle speed. I have found that I can shut it off, and let it sit for a minute,
>then restart..(no problems restarting), and I can sometimes continue for a
>while, sometimes just a few hundred yards before it does it again. If I can
>get to an exit, I can drive it all day around town with no problems.
>
>Here's what i've done so far...
>
>I changed the plugs, wires and distributor cap...no effect
>
>It did it once on the way to a job appointment, so I had to limp it to the
>nearest dealer, and got a quick rental while they took a look at it.
>They of course could not duplicate the problem, but they ran a minimum air flow
>test and it failed that, so they did an induction service, emisions flush, and
>clenaed the throttle bore and induction system of carbon deposits.
>$125...I was glad to get out of the dealer with a bill that low..lol, and I
>hoped that just maybe, that was the problem. Yep, you guessed it...no effect!
>
>Has anyone experienced this type of thing before, and can advise me furthur?
>
>Any help is appreciated.
>
>Regards, Kelly
>


--
<html><form><input type crash></form></html>
nospam@zero.com Replace nospam with jetta to reply via e-mail

Re: Please help with diagnosis...
 

Nathan W. Collier wrote:

> "Kelly J" <Kelly_member@newsguy.com> wrote in message
> news:bgk97a0tmu@drn.newsguy.com...
>> Has anyone experienced this type of thing before, and can advise me
> furthur?
>
> hi kelly,
> my money says your catalytic converter is clogged.
>
>
I'd guess clogged cat, clogged fuel filter, or fuel pump
getting ready to go on vacation. Dunno if a jeep will
do this, but on a Mazda, attempting to limp too far with
a clogged fuel filter resulted in cooking the front
catalyst to an early death.

Re: Please help with diagnosis...
 

Hi Kelly,
The computer is being thrown into the limp mode, most likely the
Crank Position Sensor:
http://www.off-road.com/jeep/cheroke...tdcsensor.html
God Bless America, ßill O|||||||O
mailto:-------------------- http://www.----------.com/

Kelly J wrote:
>
> Hi, I've got a bit of a problem with my 98 TJ 4.0l 5 speed.
>
> Here's what happens...
>
> Around town, all is fine, but once I get on the highway for a while at
> consitantly higher rpms...around 2200 or so..at 65mph in 5th, it will randomly,
> and without notice suddenly start to sputter, does a small backfire, and the
> rpms drop immediatley. Adding gas does nothing but drop the rpms faster, and
> all I can do is pull off the road before being forced to a stop in the middle of
> the highway. It doesn't die, but will just sputter away at just under regular
> idle speed. I have found that I can shut it off, and let it sit for a minute,
> then restart..(no problems restarting), and I can sometimes continue for a
> while, sometimes just a few hundred yards before it does it again. If I can
> get to an exit, I can drive it all day around town with no problems.
>
> Here's what i've done so far...
>
> I changed the plugs, wires and distributor cap...no effect
>
> It did it once on the way to a job appointment, so I had to limp it to the
> nearest dealer, and got a quick rental while they took a look at it.
> They of course could not duplicate the problem, but they ran a minimum air flow
> test and it failed that, so they did an induction service, emisions flush, and
> clenaed the throttle bore and induction system of carbon deposits.
> $125...I was glad to get out of the dealer with a bill that low..lol, and I
> hoped that just maybe, that was the problem. Yep, you guessed it...no effect!
>
> Has anyone experienced this type of thing before, and can advise me furthur?
>
> Any help is appreciated.
>
> Regards, Kelly

Re: Please help with diagnosis...
 

"L.W. (ßill) ------ III" <----------@cox.net> wrote in message
news:3F2DCFCE.50E66F4F@cox.net...
> Hi Kelly,
> The computer is being thrown into the limp mode, most likely the
> Crank Position Sensor:

hi bill,
im curious about your recommendation. every CPS problem ive ever found, the
CPS was either good or bad......ive never seen it run fine at 1 rpm and
poorly at another.


--
Nathan W. Collier
http://7SlotGrille.com

Re: Please help with diagnosis...
 

Hi Sandman,
I have, three times, on my Brother's and his Son's three different
Jeepettes.
God Bless America, ßill O|||||||O
mailto:-------------------- http://www.----------.com/

"Nathan W. Collier" wrote:
>
> hi bill,
> im curious about your recommendation. every CPS problem ive ever found, the
> CPS was either good or bad......ive never seen it run fine at 1 rpm and
> poorly at another.
>
> --
> Nathan W. Collier
> http://7SlotGrille.com

Re: Please help with diagnosis...
 

LOL....Thanks folks! Allot of possibilities indeed!!! I do appreciate the
input. I'll let you know what I find out...Wish me luck.

Regards, Kelly








LOL...ThanksIn article <fqkXa.382023$jp.10918254@twister.southeast.rr.com >,
"Nathan says...
>
>hi kelly,
>you certainly have a long list of possibilities there, hopefully one will
>solve your problem.
>
>--
>Nathan W. Collier
>http://7SlotGrille.com
>
>btw, when you figure out its a clogged catalytic converter, come back and
>let us know? ;-)
>
>

Re: Please help with diagnosis...
 

Luck.

Kelly J wrote:
>
> LOL....Thanks folks! Allot of possibilities indeed!!! I do appreciate the
> input. I'll let you know what I find out...Wish me luck.
>
> Regards, Kelly