KHarry

98 XJ sport 4.0 120k miles: I got caught in a deep mud/water pit and my cherokee swallowed some water. pulled the plugs and air filter and got most of the water out. Actually wheeled for a couple hours after the mishap and drove it home 60 miles out. Changed the oil + filter, air filter, spark plugs as soon as i pulled in the driveway.

#1 I have had a racing idle at start up (2K RPMs+) which usually drops to normal after 2-3 minutes, but its missing/stalling and sometimes races back up to 2K rpm when I'm stopped at a light. i cleaned the throttle well already.

#2 No overdrive. My tranny seems to shift at a much higher RPM now and I am not getting into overdrive. 2500 RPM's at 60 mph.

I need help, I think it is a TPS/CPS problem, need second opinion before $150+ worth of sensors without knowing for sure.

Turbo X_J

A quick search & you'll know how to test both of them. I'll bet on the problem being the former vs the later.

ZINGGG

I'd put money down that you TPS is gone. They don't like water. And when they go out, they display those types of symptoms that you are experiencing.

donkeypunch

Kharry i really hope it's a $30 tps. I am having the exact same symptoms after dunking my xj. Our circumstances and issues are the exact same even driving 60 miles home afterwards. Here is what I have found out on mine so far. I am reeeeally hoping (we) can figure this out and fix our jeeps I promise no hijacking.
Do you have any check engine lights?
Do you have access to a multimeter?
Backprobe your tps according to the tps check. The middle wire is the one that should be .02v and steadily go to 4v when manually increasing throttle, with key turned to on (not running). Mine started on 4.88v and went to 5.08v at WOT. I even checked the harness while it was unplugged from the tps. To my surprise it was the exact same as it was when it was plugged in. This has ruled out the tps I believe. If you can do these checks and compare notes it may get us both closer to solving our issues. I'm looking up how to check the ecu now and will report on my finding. Crossed fingers.

donkeypunch

I may be eating my words. My tps has just failed the ohm test. Off to the store. I'll let you know what turns out. Still odd that the harness would test so high in voltage though.

Turbo X_J

You diagnosed the problem, and then ignored it? No need to test any further, that finding should tell you without a doubt the TPS is NFG.

donkeypunch

Just for a second.
I just found it odd that the actual harness itself tested the exact same voltages in the same locations. Minus the fluctuating. I assumed id see one wire with 5v, one with very little and one at 0 or ground. Mind you this while being unplugged from a suspiciously bad sensor. I was more hoping to exchange notes with the op if he had the same readings or not. I'll definitely let everyone know the results. Thanks for everyone's help.

donkeypunch

Chomp chomp chomp. New tps makes her scream again! OP go ahead and replace it.

Thanks all.

KHarry

I'm glad you got yours humming again Donkey. I've been out of town for a week, but when I get home tomorrow, I'm gonna replace the TPS no matter what. I have had problems with them before on the ole lady's ZJ and replacing it gave us another 4mpg after only 60k miles on the original. I think its a must buy anyway, and I'm pretty sure it will solve my problems. Thanks for the recon though, and stay outa the water.

NewJerseyXJ609

Cherokees eat tps' like a fat kid eats cake. Go ahead and replace it. I have a list of things that i just replace as soon as i get any xj. lol

Check your CPS with an ohm meter. If your pcm got wet that could be an issue too.