I ran my 2002 Dakota through the car wash a few days ago with an under spray to get the salt off and when I left it ran like crap! I usually run it through the car wash during the winter at the gas station and until now, without incident. When I left the car wash it revved high and wouldn't shift. It's shifting OK now, but I have a P0123 code.

I replaced the TPS about a month ago, it's running like it did before I replaced the TPS. It will stall when cold and occasionally stumble when driving. The cruise control isn't working either, the cruise light comes on but it doesn't engage. I don't use the cruise much so I'm not certain that it is related or not. I've tried blowing out the connectors to the TPS and the APPS and as many other connectors I could see with compressed air without success.

I was hoping it would just dry out but it hasn't changed in driving it all week.

Any ideas? If I can't figure it out should I go the dealer or can an independent shop handle this?

Thanks

 

well, p0123 is something to do with tps sensor voltage. ive had that on my truck before. since you said you've had these symptoms before and now its acting like it did when the tps was screwed up, i'd say you've got a problem with the tps again. maybe you fried it when you went through the car wash.

 

How do you fry a throttle position sensor going through an automated car wash? I'm not trying to be mean, I'm just curious. It's under the hood. I could understand if you were washing your engine bay that could happen, but it's an auto car wash.

I'm sorry, really not trying to be rude... I just don't understand how that could happen. Is it right under the wiper cowl or something?

 

Im with CSC... doesn't make a whole lotta sense... possible but not nessesairly plausible.

 

It's not running exactly like it did before I replaced the TPS. It was throwing code P0121 then and if I reset the codes I could drive a few blocks before the check engine light came on. Now if I reset the codes the check engine light comes on immediately. I thought about replace the TPS again, but I'd rather not throw parts at it hoping something will stick.

I suppose its possible that the car wash wasn't the cause and it was just coincidence, but that seems odd.

 

The other day i went through a car wash and then when I got out i had no head lights, 4 wheel drive, power anything, interior lights... just blinkers and brake lights. I was about to kill somebody. I went back to my girlfriends house and unplugged the negative terminal of the battery, hooked her back up 10 min later and luckely it all worked again. It had me so nervous...

Probably doesn't help you any seeing they are different problems, but those automatic car washes can screw things up sometimes.

 

not sure how a car wash could cause the TPS thing, but i know what your problem is bpark, you got moisture in the CTM. the CTM controls all those things you just said. my friend's 02 4.7 would do the same thing when it rained heavily. eventually after the stuff dried out it would all work again, but one day it happened and the stuff never worked again so he ended up having to get the CTM replaced.

 

does your truck have a stock air intake?
If you added a CAI you might just have to dry out your system.
If it is stock, check the aircleaner to see if you sucked up water.
remember your truck was running at the time, and water was spraying everywhere it could.
Think Simple first, then move onto the tough stuff.

 

Gary has a point, that underbody spray couldve messed something up... However i have hit 4inches of standing water at about 60mph (not on purpose or anything) and didn't have any trouble with my CAI, ya it scared the bejesus out of me but the truck worked fine...

What i am trying to say is that its possible but in most cases probably not harmful enough to where it would throw out your TPS

 

I took the truck to some guys who specialize in electrical issues and it turns out it was the aftermarket Throttle Position Sensor I had installed a month or so ago. It read wide open even with the engine off, that's why it ran like crap and the cruise control didn't work.

He said to only use the OEM sensors. The aftermarket sensors are Chinese garbage.

Lesson learned. Thanks for all the suggestions.