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1991 Pontiac Grand Prix, IC Circuit Waveform
Posted to the Waveform Library on 8/31/2001

Vehicle had code 42 set hard. This was a single capture taken at start up. You can see during cranking during 'module mode' that the EST line is being held low like it should by the module (about 500mv peak). When the RPM hits roughly the 400 RPM range the ECM...

 

car Vehicle Data

1991 Pontiac Grand Prix SE 3.1L

Engine3.1 L / 6 cyl / GAS
Trans4-speed AutomaticTransaxle
DeliveryFuel Injection
SubsystemECM/Inputs/Outputs
Component
ConditionKnown Bad

car Vehicle Data

1991 Pontiac Grand Prix SE 3.1L

Engine3.1 L / 6 cyl / GAS
Trans4-speed AutomaticTransaxle
DeliveryFuel Injection
SubsystemECM/Inputs/Outputs
Component
ConditionKnown Bad