Wtf did I do?! Pressure washed engine bay now jeep idles at 2000 RPM
10-16-2015, 06:15 PM
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Wtf did I do?! Pressure washed engine bay now jeep idles at 2000 RPM
Hello all, 98 4.0 automatic Cherokee, pressure wash the engine bay today taking care to avoid blasting anything electronic directly, upon restart Jeep now idles uncontrollably at 2000 RPM and unplugging the TPS has no effect whatsoever, unplugging IAC has no effect, unplugging map sensor it almost stalls but when you plug it back in it runs right back up to 2000 , pulled the covers off the ECU plugs and blasted everything with air to try and get any unwanted moisture out of places it may have gotten. restarted and it idled normal then revved itself three times and stuck at 2000 RPM again... Help! I'm stuck at the car wash trying to figure this out
10-16-2015, 06:32 PM
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10-16-2015, 06:41 PM
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What's even stranger is when I unplugged the throttle position sensor the ScanTool still shows 100% throttle position sensor output
Did I cook the computer?
Did I cook the computer?
10-16-2015, 07:06 PM
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I don't think you cooked it. I agree with Serious, you have a leak somewhere. Do you check the throttle cable? Make sure its fully retracted.
10-16-2015, 07:39 PM
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10-17-2015, 05:30 AM
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Exactly what I'm going to do, it's definitely misbehaving in a very erratic form, I have never watched engine rev itself twice and then suddenly surge to 2000 RPM , kind of like it's possessed LOL
the only thing that I have ever seen similar to this before is whenever I power wash the Datsun's engine bay I have to take great care to not hit the alternator , as the Saturn SC2 96a alternator I have on the engine is highly sensitive to water and once wet will put out over 20 V DC ...
the only thing that I have ever seen similar to this before is whenever I power wash the Datsun's engine bay I have to take great care to not hit the alternator , as the Saturn SC2 96a alternator I have on the engine is highly sensitive to water and once wet will put out over 20 V DC ...
10-17-2015, 06:46 AM
#10
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The TPS itself is still suspect here. It is a component that hates water; lots of posts on this and other forums about it. You could try removing the TPS connector and flushing it with electrical contact cleaner, but if moisture has made it into the TPS, then usually it must be replaced. If at the end of the day you replace your TPS, do yourself a big favor and buy a genuine Jeep TPS.
10-17-2015, 07:01 AM
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The TPS itself is still suspect here. It is a component that hates water; lots of posts on this and other forums about it. You could try removing the TPS connector and flushing it with electrical contact cleaner, but if moisture has made it into the TPS, then usually it must be replaced. If at the end of the day you replace your TPS, do yourself a big favor and buy a genuine Jeep TPS.
10-17-2015, 08:21 AM
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Next time you want to wash your engine, don't pressure wash. Use a quality degreaser, scrub with a brush, and gently rinse. Covering your electrical components would be a step better. Steam cleaners can do a pretty great job as well as long as you're patient and aren't blasting it with too much pressure.
10-17-2015, 08:29 AM
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Next time you want to wash your engine, don't pressure wash. Use a quality degreaser, scrub with a brush, and gently rinse. Covering your electrical components would be a step better. Steam cleaners can do a pretty great job as well as long as you're patient and aren't blasting it with too much pressure.
11-03-2015, 12:42 PM
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I would agree a little with everyone, let it sit, but the tps sounds like the culprit. i replaced one in my buddys 2001, after it was all said and done, the jeep gets a mind of its own and revs a few times and then sits at a crazy idle, but the fact that you said it revs itself a few times tells me its the tps. hope she ends up okay after letting it sit, but hope for the best, prepare for the worst.
