1991 corvette bad idle
sheriffjim
05-07-2022, 11:51 PM
Howdy! I'm new to this forum. I've been fairly active on the corvette forums but have had no success. Maybe someone here can help.
My car idles badly. The idle drops and usually recovers, however as the car gets hotter the idle gets worse and will eventually stall. It also runs rough in the lower RPMs, but runs great past about 2k RPM.
Unplugging the MAP sensor fixes the idle, but the car won't rev without it. The map sensor voltage and pressure are both within range.
Tunerpro indicates my 02 sensor value is not changing, its about 452. I replaced the 02 sensor, and the value didn't change. I unplugged the sensor and the value didn't change. The SES light didn't come on either. So I think the computer still thinks the sensor is there. Maybe this is the problem? I have no idea how this could be happening.
TPS is adjusted correctly and working, so is IAC.
Hopefully I can get some help. Thanks!
My car idles badly. The idle drops and usually recovers, however as the car gets hotter the idle gets worse and will eventually stall. It also runs rough in the lower RPMs, but runs great past about 2k RPM.
Unplugging the MAP sensor fixes the idle, but the car won't rev without it. The map sensor voltage and pressure are both within range.
Tunerpro indicates my 02 sensor value is not changing, its about 452. I replaced the 02 sensor, and the value didn't change. I unplugged the sensor and the value didn't change. The SES light didn't come on either. So I think the computer still thinks the sensor is there. Maybe this is the problem? I have no idea how this could be happening.
TPS is adjusted correctly and working, so is IAC.
Hopefully I can get some help. Thanks!
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