Hello,
Just wondering if I could get some help. I have a 1997 accord. 4-cyl. Runs great, but when stopped at stop light/idle it will rev up and down from about 1,000 to 1,500 rpms. Changed out the PCV valve and MAP sensor with no change. Although after changing out the MAP sensor, it has gotten better. Any ideas????

 

Hello, and welcome. The mods will probably relocate this thread to the general help forum, where you'll get a quicker response (tends to be checked more frequently than the welcome forum, I've found).

First question: Is your check engine light on?

 

Check out this thread about setting your base idle.
https://www.hondaaccordforum.com/for...e-speed-38734/

And Derek's right, I'll move it over to Gen.Tech.

 

Thank you, and no, the check engine light isnt' on.

 

Cyclic idle speed can be caused by a number of things, but most frequently the cause is air leak. Check PCV, vacuum line to brake booster, and other vacuum lines for leaks.

Also low coolant level can occasionally cause this problem. Make sure coolant level in reservoir and radiator is good. Check cold condition!

good luck

 

Hello,
Just wanted to update....
First of all, thank you for the ideas. Apparently the first problem was air in cooling system. Then cleaned throttle body and such. Then followed the detailed instructions on getting the system reset and voila!! Car runs great now.