Engine idling too high

Hello,

It sounds like the MAF sensor needs to be replaced or the throttle bore needs to be serviced. Here are two guide I want to run through.

https://www.2carpros.com/articles/engine-idles-too-high

and

https://www.2carpros.com/articles/how-to-replace-a-mass-air-flow-sensor-maf

Please run down these guides and report back

Cheers,

Thank you for this post, nobody can figure it out but I did LOL I serviced the throttle body and the problem went away! I love this site.

My truck idles very high. Had idling valve changed 5 times. When im driving I can feel the engine revving high.I pull over and put it n park and my RPM goes up to 2000+.I need help bad

Clean throttle plate on both sides with choke cleaner and iac hole, then check for a vacuum leak like hose off /broken etc.

I have a 05 Aztek and it has recently started idleing at 1500 in drive and 3000 in park. I have replaced the Throttle position sensor and that has not fixed the problem. Any suggestions that could help? Thanks in advance.

Hi:
Is the check engine light on? Also, did you check the idle air control valve (IAC)? Without a code, it could be a few things. If the light is on, have the computer scanned at a nationally recognized parts store. Most will do it for free.

Let me know what you find.

Joe

My problem just occured today. As I was leaving the store I approached the red light and when I braked to stop, my car started to rev up to 3000 rmps and would not stop. I live 12 miles away from the store I was at and at every stop sign or light, my car would slow down normally and then when I was at a complete stop, the rpms would jump and it was if I had the brake and gas on at the same time! What the heck could be causing that?

If you haven't had it looked at yet, a scan tool that shows engine data will be the primary source of your diagnosis. Barring the basic checks, floor mat wedged on pedal, giant vacuum leaks from the engine making a loud hissing noise or the air filter lid left off of course.

If you can get access to a scanner check the throttle position sensor position (tps) first. At a stop with your foot off the gas it should read 0.0 volts. If the engine sees the sensor too high it believes the gas pedal is being pushed and will compensate by adding fuel, which causes the idle control to compensate for near stall from a rich condition and you have a high engine revs.

Post back if you need further assistance.

Good luck.

Thanks for the reply. The actual problem was coming from the idle arm control motor. It was very dirty and once cleaned and put back together, my problem stopped. I ended up putting a new throttle posistion sensor on it anyways because I already purchased it.

I have a new problem now. Car overheats after one mile of driving it, the radiator cap doesn't get hot, it is leaking a small amount of antifreeze. The heat works and then it doesn't. I am not sure why the engine gets so hot so quickly. The antifreeze overflow isn't being used when the engine overheats. Could my thermostat or water pump be going?

Excellent work on the Idle Air Control! I am certain we can figure this new problem out. We'll start with a couple of checks and questions to get started.

1) Does the overheating occur after 1 mile even when started cold? (Has sat for at least 3 hours)
2) Is the overheating symptom the gauge, and if so where is the needle rising to?
3) Is the overheating symptom steam from the engine?
4) What are the coolant levels for the radiator and overflow tank? FYI the overflow tank often looks as if it has fluid but is just a small bit that wouldn't drain. You can verify if fluid low in the radiator by filling and noting how much it needed. Add slowly and allow time for air to escape.
5) If the fluid is about 1 gallon low, pressure test the system with a pressure tester while the system is full and inspect under the hood and on the ground for the source of the leak.

Here is a site link for the basic coolant checking. http://www.2carpros.com/first_things/coolant_leaks.htm

I've probably overloaded you for now so, post back and we will proceed with the diagnosis.

Regards,

Intermittently idles high at 2000 to 4000 RPM
when stopped and in park. When engine is shut off and restarted it will idle normal. Throttle
is not sticking.

Clean the throttle-body and idle air control. Check for any applicable trouble codes. Check the TPS. Check for vacuum leaks.

When the problem occurs, if you block off the mouth of the throttle body, any effect on the idle? With intermittent issues, you have to check when problem is ongoing.

My rpm revs up to high when in park - put in drive and it comes down somewhat but is still high - what could be wrong and how can it be fixed? Thank you - Debi

Possible idle air control motor failure or a large vacuum leak

Roy