Another 85 that surges @ idle...
Thread Starter
Pro
Joined: Jun 2001
Posts: 520
Likes: 6
From: Elverson PA
I have been fighting idle problems since I got my car. I always get it straightened out for awhile, but then the same thing. After prolonged idle or even if the car is a little warm, the idle will vary from 500-700.
When I pull out the pcv it smooths out. If I pull of the vacuum from pcv, the car dies. The pcv is new as of today. Also, runs smooth if started with maf unplugged. I don't know if it is related, but car acts like it did when it needed a new maf only no codes. I did get a rebuilt maf w/ lifetime warrenty. Tpis said they have had rebuilt ones causing this situation. One other thing....could a bad o2 sensor cause this surging? Maybe I need a heated one (see signature). Thanks in advance!
When I pull out the pcv it smooths out. If I pull of the vacuum from pcv, the car dies. The pcv is new as of today. Also, runs smooth if started with maf unplugged. I don't know if it is related, but car acts like it did when it needed a new maf only no codes. I did get a rebuilt maf w/ lifetime warrenty. Tpis said they have had rebuilt ones causing this situation. One other thing....could a bad o2 sensor cause this surging? Maybe I need a heated one (see signature). Thanks in advance!
Team Owner
Joined: Dec 2000
Posts: 90,675
Likes: 304
From: SE NY
Cruise-In II Veteran
In any case with headers a heated O2 sensor is a good idea.
Normally I would suspect false air or a bad IAC. But unpluging the MAF points to the MAF as the issue.
Here a scan tool would be very helpful as you could monitor sensor data and see if the IAC is hanging up or the MAF is sending bogus info.
Normally I would suspect false air or a bad IAC. But unpluging the MAF points to the MAF as the issue.
Here a scan tool would be very helpful as you could monitor sensor data and see if the IAC is hanging up or the MAF is sending bogus info.
