Lately my 1998 3.0L has been idling really weird at some points, like ill be driving down the road and it will jump to 3000rpm when i press in the clutch and stay there until i come to a stop then it will only go down to 1500rpms and it will stop when i kill the engine then restart it or take it over 4000rpms... Any ideas on what it is??

 

Idle Air Control valve.. Dirty MAF sensor.. or you could just disconnect the battery for a couple of minutes and see if resetting the PCM helps.

 

Ok. Thank you

 

Ya my 98 3.0 was doin that for a while lol
I just cleaned the IAC valve and no problems!

 

My 2000 did that quite often before I changed the IAC, it was pretty annoying esp. with the loud exhaust. I tried to change gears real quick just to keep it from reving when I pushed in the clutch. Good luck, and let us know if it works for you.

 

ya i try to do that too. This may sound stupid but whats the IAC valve?

 

Idle Air Control. Basically when the engine isn't under load it adjusts the idle speed.