Odd problem with 98 TJ

Oct 31, 2005 14 Replies
K

Hi,



I have a 98TJ 4.0L with 5 speed. 97,000 miles



I have an intermittant problem the engine. It only happens on occasion (maybe once a week) and ONLY after 30+ minutes of sustained highway speeds. The engine will sudenly begin to stutter, and keeping the foot in the gas will just drop the revs faster. I just have to press in the clutch and coast to the side of the road. Once off the road, it will idle smooth as silk, no danger of stalling, and if I sit there idleing for just a minute or two I can continue with no problem.



I had a similar problem a couple of years ago and finally tracked it down to a bad Crank Position sensor. Since this problem was so similar, I went ahead and put a new CPS in but the problem still remains. I thought it might be bad gas, but several tanks from differant locations and a couple of bottles of fuel system cleaner have not fixed it. Although I would think that bad gas or a clogged filter would give a more consistant, and sustained symptom. Any other ideas??



Thanks for your help.



Kelly



98TJ
2" suspension
1" body truetrak in dana 35
32" Super Swampers
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K

Hi Jerry, That's what i thoought at first, so as i said, that was the first thing I replaced. I have a spanking new CPS in there, but the problem still persists. I did save the old one so at least i have a spare now.

Regards, Kelly

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M

Umm, you do know there are two 'CPS's right?

One is under the distributor and is called the Cam Position Sensor, the other is on the driver's side bell housing and is called the Crank Position Sensor.

Mike

86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail >
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J

Yes I know you replaced the crankshaft position sensor, I was suggesting the camshaft position sensor should be the next logical step. It's mounted inside the distributor, just underneath the plastic shield underneath the distributor cap.

Jerry

Kelly wrote:

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K

My apologies, thought you meant the crank sensor. I have not heard of a cam sensor. I will look into that for sure Thanks.

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J

You might also want to check the TPS.

This is a problem that some of us have been having off and on. As far as I know, no one who has had it (who has the original engine) has ever truely figured out the problem. It hardly ever will do it for the shop. You have to have the scanners hooked up and running when it does for them to see it.

On mine, which does NOT have the original engine, we ended up having to clock the distributor to stop this problem. The shop thinks it was either the wrong crank or the wrong cam for the engine...thats what I get for going with a cheap rebuilt. My rig litteraly spent months in the shop while they tried to figure it out.

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C

try unplugging the TPS several times. It may just need a bit of oxidation removal from the pins...

cal

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K

Thanks Cal, that sounds like an easy and inexpensive thing to try. pardon my ignorance, but what and where is the TPS? I really need to invest in a Jeep shop manual:-)I hate Chiltons and Hanes books and to be honest i haven't even seen one of those available for the 98 wrangler.

Kelly

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P

fuel pump can't keep up

Kelly wrote:

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K

Thanks for the tip, I forgot about ebay. I just baught a shop manual for the

98TJ >
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P

Your welcome Kelly. Now burn me a copy so I can use it with my 97 TJ Email my user name to yahoo Steve

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