Q: idle is high after driving

asked by on

i am stumped as to why my 92 ford explorer idles very high after driving it. upon startup, it will idle around 500-700 rpm. after i drive it for any fair amount of time (5 miles or more), i will shift into park and the idle goes up to around 1000-1200 rpm. just did an oil change recently, brand new spark plugs, checked pcv valve (still good). no vacuum leaks. what could be the issue?

My car has 243000 miles.
My car has an automatic transmission.

Hey there. Normally a vacuum leak is the most common cause of a high idle but many issues may cause this. Other possible causes of a high idle are improper sensor inputs, an idle air control valve, a faulty engine coolant temperature sensor, a stuck throttle body, a throttle body cable stuck, a bad power steering pressure sensor, AC high pressure sensor or a problem with the ECT (electric control transmission).

As you can see, many different systems cause a high idle condition. With the high idle not occurring until after the vehicle has been heated up, it appears there may be a heat related fault such a sensor reading improperly once it gets hot, or an intermittent issue with the IAC sticking sometimes. A complete inspection will be the easiest way to diagnose your high engine idle.

Was this answer helpful?

Need advice from certified mechanic? Get help now!

Over 1,000 mechanics are ready to answer your question.
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details
  1. Home
  2. Questions
  3. idle is high after driving

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

Get a quote

What others are asking

Q: Vehicle won't go into gear when running, when turned off, vehicle will go into gear but won't start. 1998 Ford Explorer

Hello - your clutch hydraulics are the problem here. Check the clutch hydraulics fluid level - and it may share the same reservoir as the brake master cylinder (both use brake fluid as the hydraulic medium). If fluid needs to...

Q: How do I turn the rear park aid feature on or off?

The rear park aid is a safety feature that helps you when you are parking or are in a reverse situation. When in reverse it audibly alerts you of your surroundings, and how close you are to hitting other cars...

Q: I Had a diagnostic test for Ford escort. What can I do about the Mass Air Flow sensor?

Hi there. You can remove and clean the Mass Air Flow sensor with an electrical cleaner that is non chlorinated. If the sensor is cleaned out and the light is still on, check the intake hoses from the sensor to...

Related articles

P0052 OBD-II Trouble Code: HO2S Heater Control Circuit High (Bank 2 Sensor 1)
P0052 code definition HO2S Heater Control Circuit High (Bank 2 Sensor 1) What the...
Rules of the Road For Iowa Drivers
Driving on the roads requires knowledge of the rules, many of which are based on common sense and courtesy. However, even though you know the rules in...
P2428 OBD-II Trouble Code: Exhaust Gas Temperature Too High Bank 1
P2428 code definition A P2428 trouble code signifies that the PCM has detected a problem in the exhaust gas temperature sensor circuit in bank 1, which subsequently contains the number one...