hey all,
is it possible that a bad gasket on the egr valve could cause the idle surge when the car is warm? ive checked the usual suspects (iacv, fitv, both checked out ok), and when checking for leaks by spraying with carb cleaner, as i sprayed around the base of the egr valve, the car almost died. i didnt think that the egr system mattered to idling that much...im going to pick up a gasket tonight and try and replace it, to see what happens.
also, i tried following the instructions on how to reset the base idle (with the car warm unplug the fitv connevtion and then turn the idle screw to between 450-550), but with the idle screw all the way in the car has a steady idle of 1000 rpm...with the plug connected, it idles warm around 1500 rpm...any other way to adjust the idle? i know its not supposed to idle that high!!! thanks for any help in advance, and sorry for the long post...
car is a 1995 ex 4cylinder if it makes a difference...

 

Make sure your throttle cable is adjusted properly and generally not binding.

 

Well, what I learned is that EGR doesn't operate during idling or at WOT. It's during normal speed operation if I can remember correctly. You don't want EGR at idle; otherwise, the car will sputter and die.

But since you did that, I'd go ahead and replace the EGR valve gasket. Just be sure the old gasket is off and that the mating surfaces are smooth before putting on the new one. Good Luck!

 

Yes. If your egr gasket is leaking in the right place, manifold vacuum will draw air in through the runners acting exactly like a vacuum leak.

 

Well, it's obvious that the EGR gasket was leaking. You still have a vacuum leak somewhere. Check around the intake manifold, plenum, and throttle body gaskets if you haven't already.

 

Also check the rubber seals for the IACV and FITV, if they are flattened or dried out/cracked they can leak into the manifold as well.