engine idling with hesitation at stops. Why?

robblaw · 11-30-2004, 09:52 PM

Whenever I am at a stop light the engine on my 96 SL2 automatic seems to idle ok for a second and then a kickback or misfire occurs. Its like a hesitation or hiccup and it is driving me crazy. The engine continues to idle as usual and the hiccup happens again and again at different times until I am in motion. What could it be? Please help me.

Mr.Resist0r · 12-01-2004, 03:14 AM

is it throwing any codes? I would say your EGR is sticking, just give it a few pushes and see if it clears it up.

Anony00GT · 12-01-2004, 07:07 AM

EGR valve is only open between 1200-2400 RPM, but the GM ones do have a habit of sticking, so checi it, since it only takes 10 seconds and can't hurt.

I'd suggest looking for vacuum leaks or air leaks, and also checking the MAP sensor.

robblaw · 12-01-2004, 10:34 PM

Don't know if it is throwing any codes don't have a tool. I just got a new EGR valve. Give what a few pushes, the EGR valve? The RPM needle does go down and back up above 1 when this occurs. There is also a brownish/orangish gunk around the end of the valve and inside the case it goes into. This stuff is also present in and around the coolant area. How do you check the MAP sensor?