86-ZZ3
Well-known member
My '86 TPI has been having intermittent high idle problems. A few months ago, I reset the idle speed + adjusted the TPS. All was fine. In the past few months, the engine would start and idle high. Lately, it's been running really high. I've just cleaned the throttle body (on car and off), tried to clean the old IAC (no result) and replaced the IAC (no difference).
Once the engine starts, it will either stay at that high idle range (1900-2000 rpm - most engine starts) or goes down to about 900 (lately about 1 in 7-10 starts) and doesn't fluctuate so I don't think it's a vacuum leak issue. The engine pull when the idle is normal is quite pronounced so the car doesn't slow down much in idle (700R4) unless I brake when the idle will go down a notch.
I can't figure out what the problem is. I've also taken the car for a drive to warm it up and run it above 40 mph at steady throttle (supposed to
seat the IAC), and also reset the ECM by disconnecting the battery for a minute.
ANy hints/suggestions? I've done a search of previous problems posted and solved and kind of hope it isn't the EGR.
Once the engine starts, it will either stay at that high idle range (1900-2000 rpm - most engine starts) or goes down to about 900 (lately about 1 in 7-10 starts) and doesn't fluctuate so I don't think it's a vacuum leak issue. The engine pull when the idle is normal is quite pronounced so the car doesn't slow down much in idle (700R4) unless I brake when the idle will go down a notch.
I can't figure out what the problem is. I've also taken the car for a drive to warm it up and run it above 40 mph at steady throttle (supposed to
seat the IAC), and also reset the ECM by disconnecting the battery for a minute.
ANy hints/suggestions? I've done a search of previous problems posted and solved and kind of hope it isn't the EGR.