I have a 1990 Olds Cutless Supreme, I have problem with RPM drop.
3 Answers
IAC valve sluggish , carboned up
1 people found this helpful.
Possibly dirty iac. But if running fine with ac on I tend to suspect dirty throttle plate causing your issues.
1 people found this helpful.
Best Answer
Mark helpful
It was the dirty throttle plate. Sprayed Carb & throttle cleaner and watched the dirt run out. Did this 5 or 6 times and took for a 20 mile test run and it runs like a charm. Thanks