Code 53, EGR Control Error
During normal operation, ECM compares its EGR duty cycle signal with the MAP absolute pressure signal and makes corrections in the duty cycle accordingly. If actual EGR control pressure (line vacuum) varies more than 2.4 in. Hg from what ECM has previously determined pressure should be, and variance continues for more than 10, Code 53 will be set. ECM will shut down EGR. The "CHECK ENGINE" light will remain on and EGR off until ignition switch is cycled off.
NOTE:
The following step numbers refer to the numbers in the accompanying flow chart(s).
- Checks if adequate control signal vacuum is available to MAP sensor.
- Tests MAP sensor's ability detect a variance in control signal vacuum and adjust voltage output accordingly to ECM.
- Determines if EGR control error was detected and Code 53 set due to EGR Solenoid malfunction or MAP Sensor problem.