Turshin
Probationary Member
- 18
- 0
- Oct 27, 2018
-
Romulus,
Michigan
Just got my 1g GST home from the shop after getting the head rebuilt and instainstalled. Turn the key, no start. Turn it again nothing. Turn it for a third time and it cuts on and shoots to 2k rpm. My first thought was vacume leak. The throttle modulates between 1500 and 2000 rpm. Gradually as the car warmed up and the rpm settled down. Fumbling and stumbling around 750 rpm. Did some research while sitting in the car about the symptoms my car was having. FIAV, ISC, and vacuum/boost leak kept coming up in my searches. Let the car for 20 mins and noticed the idle was stumbling around 600 rpm but didnt stall. Eventhough i know the motor mounts are good, the engine was still shaking a bit. I reved it up to 3k. It shook a bit and stumbled and acted like it wanted to stall out initially but when it got past 1500 rpm it smoothed out. So i took it for a drive. Same thing happened when i pulled out in 1st. Initial stumble and fumble and then smooth. Shifted to 2nd and felt the boost kick in pretty good at 3k rpm. As i slow down and come to a stop the idle still stumbles around 600 rpm. I get home and order up a new ISC. I noticed i had the brown one and swapped in a black one. Problem remained. I only have any type of idle surge during a cold start. So i ruled out the FIAV. Ran the smoke machine on it and no vacuum leaks were found. What could be causing my terrible idle?