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Technician Chris
Technician Chris, Technician
Category: Car
Satisfied Customers: 425
Experience:  I am a certified ASE Master Technician with L1 Advanced Diagnostic Specialist and over 15 years experience.
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Wrangler: 92 Wrangler 4.0 manual trans 4wd. Hi idle at start

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92 Wrangler 4.0 manual trans 4wd. Hi idle at start up.
I would start by checking for any vacuum leaks. With the engine running, do you hear any "hiss" noise under the hood? If so , there is a vacuum leak that needs to be plugged. Are there any other issues with the Jeep? Does it run ok other than just he high idle?
Customer: replied 3 years ago.
No vac leaks. Runs great otherwise. I'm using a snap on solus and there's no codes. Tps shows 2.25 at idle. Is that too high? Idle comes down after a while. Sometimes in a minute. Sometimes longer. Engine temp doesn't seem to matter.
That reading at idle is definitely too high. It should be around 0.5V - 0.7V. At WOT, it should read about 4.0- 4.5V. What is WOT reading? Even at 50% throttle, the reading should only be about 1.8V - 2.0V. Make sure the throttle plate isn't sticking open and the reading is actually correct. If the plate is normal, then it sounds like a faulty throttle position sensor. Check the sensor, perform a throttle body cleaning to get rid of any sticky carbon build up and if nothing changes, replace the TPS.
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Customer: replied 3 years ago.

I'll do that again and reply later.
ok / let me know the outcome
Technician Chris and 6 other Car Specialists are ready to help you
Customer: replied 3 years ago.

Removed the tps from the throttle body and checked it manually with the scanner. Readings were all over the place. Replaced it and all is well. Thanks for the help.
Glad I could be of assistance. Thank you for the rating.