now that i have put in a tach (thanks das) i can actually see the strange idle...

i was wondering what normal idle is? say in park. or at a red light.

my car, in park, goes from 8-900 to 1,000 up and down. about 10-15 second or so intervals. I have heard this many times but never knew the actual rpms.
today, when i started the car, i was on the phone, so i was watching it. it was doing the 10-15 second thing and then its would stay, steady at 1,000 for 2-3 minutes. and go back to up and down for a few minutes. then back to steady again and so on........

ummm, normal? not normal? what is it doing????

 

Could be a vaccuum leak. Check all your lines. They are hard plastic and tend to become brittle under the harsh heating and cooling of the engine.

Also, I dont know if a sticky EGR valve can cause it?

Throwing any codes?

 

Mine does that as well, but its never stalled out or anything, also the check engine light doesnt come on and no codes come up

 

just 12. i disconnected my battery the other day.

 

Listen to if your rad fan(s) come on. I have two, and I know when they turn on at an idol, it lugs down from 800 a bit then goes to 1000 and holds till they shut off.

I also had a rad fan relay problem which caused them to turn on whenever they pleased, being that the engine was only running 30 seconds from a cold start and they turn on for some reason. Weird enough, it went away when I cleaned my MAP. So it surged as your describing.

Check it out, wouldnt hurt.

Sean