2000 Auto Ex here...300-400 (MSD produced) pretty cool

 

I have to agree with the vacuum leak theory. That's exactly what happened when the vacuum line kept popping off of my FPR.

 

Mine idles around 600-700, but sometimes it drops way down, like really low. What could be causing that?

 

If you have PS, the pump can burden the motor when you turn the wheel and it will drop your idle. It could also be bubbles in the coolant (from what I understand).

 

I do have PS. Could it be anything else like a bad fuel pump or clogged fuel filter? It goes really low sometimes (almost the very bottom of the tach) but it hasn't stalled.

 

it's your fast idle valve under your throttle body where the two coolant lines connect to. use an 8mm wrench to open the cover on the back side and turn the valve in a little while the car is running. HAd the same problem before

 

Okay, no one had a throttle body gasket and the dealer was closed so I made my own :thumbup: Must be that. Seems like it sealed pretty good though. That's what i get for riggin it up like a dumbass. I thought a vacuum leak would make it idle crazy, not a steady high idle.