high idle problem?

2000 SATURN SL2

4 CYL • FWD • AUTOMATIC

AA3493

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I have a 2000 Saturn SL2 and it seems like it idles high while driving. The idle will slow down after holding the brakes to a stop and when you are just sitting in one spot but when your driving it seems like it doesn't want to slow down. It is showing a code of P0404 which is a egr fault. What should I do?

Nov 18, 2010 at 2:47 AM

SQM

CERTIFIED EXPERT
6,383 POSTS

Hello,

It sounds like you might have a faulty Idle air control valve (IAC).
The IAC control the idle and a faulty IAC can cause the idle to be unusually high.
Many times cleaning out the valve will fix the high idle issue. Simply take the IAC off of the throttle body and clean it out with good quality parts cleaner. Wait for everything to dry and reinstall.

Here are some helpful article on how to service the IAC:

https://www.2carpros.com/articles/how-a-idle-air-control-valve-works
https://www.2carpros.com/articles/idle-air-control-valve-service
https://www.2carpros.com/articles/engine-idles-too-high

For the P0404, typically you will get that code if the EGR valve is clogged.
You can also clean out the EGR as well.

https://youtu.be/DqUCbbKdWf4

I have also attached the diagrams for the IAC and EGR

Please let me know of any questions.

Thank you.

Images (Click to enlarge)

Aug 4, 2021 at 9:58 PM