SES Code 32
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Intermediate
Joined: Apr 2009
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From: Huntington Beach California
SES Code 32
I have a '90 coupe L98, all stock except previous owner installed what appears to be MAMO cat back exhaust with crossover (2.25" pipes).
I'm getting an intermittant code 32 (EGR) and wondering if the reduction in backpressure due to the cat back exhaust could be causing it? I smogged the car (Calif car) a month ago and all emissions were a fraction of the allowables both at idle & 2500 RPM tests. Just wanted to check if this exhaust could throw this code before I go through the diagnostic tree. Seems to happen at medium to heavy throttle, but only intermittingly.
Thanks for any input.
I'm getting an intermittant code 32 (EGR) and wondering if the reduction in backpressure due to the cat back exhaust could be causing it? I smogged the car (Calif car) a month ago and all emissions were a fraction of the allowables both at idle & 2500 RPM tests. Just wanted to check if this exhaust could throw this code before I go through the diagnostic tree. Seems to happen at medium to heavy throttle, but only intermittingly.
Thanks for any input.
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A Helpful Explanation of the EGR Switch and ECM Code 32:
Exhaust Gas Recirculation valve is operated by vacuum which is supplied by the EGR vacuum solenoid. The ECM (electronic control module) grounds the solenoid as needed and releases vacuum to the EGR valve. The ECM looks at the information from the coolant sensor, mass air flow or MAP sensor, engine RPM, and TPS (throttle position sensor).
There should be no EGR when in park or neutral, TPS input below a specified value, or the TPS is showing wide open throttle.
Code 32 is set in the ECM when these conditions are met:
Coolant temperature greater than 80°C (176°F).
EGR duty cycle commanded by the ECM is greater than 75%.
TPS is less than one-half throttle, but not at idle.
Codes 21, 22, 23, 33, 34 not present.
All conditions above must be met for about four minutes.
A defective EGR switch is the most common cause of code 32. It doesn’t go to ground when the EGR pipe gets hot after the EGR valve opens. The “Check Engine”, code 32, will probably never come on in the city. It usually occurs after driving six or seven miles at a steady rate.
The fix is to replace the defective switch. On the 1985, the switch is located on the EGR valve under the air plenum. On the 1986-89, the switch is located on the right rear of the engine’s covered EGR bypass pipe. The 1990-91 L98 does not have an EGR switch; but, it still has an EGR valve.
Exhaust Gas Recirculation valve is operated by vacuum which is supplied by the EGR vacuum solenoid. The ECM (electronic control module) grounds the solenoid as needed and releases vacuum to the EGR valve. The ECM looks at the information from the coolant sensor, mass air flow or MAP sensor, engine RPM, and TPS (throttle position sensor).
There should be no EGR when in park or neutral, TPS input below a specified value, or the TPS is showing wide open throttle.
Code 32 is set in the ECM when these conditions are met:
Coolant temperature greater than 80°C (176°F).
EGR duty cycle commanded by the ECM is greater than 75%.
TPS is less than one-half throttle, but not at idle.
Codes 21, 22, 23, 33, 34 not present.
All conditions above must be met for about four minutes.
A defective EGR switch is the most common cause of code 32. It doesn’t go to ground when the EGR pipe gets hot after the EGR valve opens. The “Check Engine”, code 32, will probably never come on in the city. It usually occurs after driving six or seven miles at a steady rate.
The fix is to replace the defective switch. On the 1985, the switch is located on the EGR valve under the air plenum. On the 1986-89, the switch is located on the right rear of the engine’s covered EGR bypass pipe. The 1990-91 L98 does not have an EGR switch; but, it still has an EGR valve.
