Pcm Code P034 - Map Sensor Signal Too High: Action
PCM turns on SERVICE ENGINE SOON light. PCM uses a substitute MAP sensor value based on engine RPM and throttle position switch status. PCM disables long term fuel trim.
NOTE:
Test numbers refer to numbers on diagnostic chart.
- MAP at idle should be 30-50 kPa, depending on engine load. BARO pressure should be 85-105 kPa, depending upon altitude.
- Check for vacuum at fuel pressure regulator hose. At idle, typical vacuum reading should be 14-20 in. Hg, depending on engine load.
- Checks for faulty MAP sensor vacuum supply or MAP sensor circuitry.
- Checks for open sensor ground from sensor to PCM.
- Checks for short to voltage on sensor signal circuit No. 432.
- Fault is at PCM connector or PCM. Check for damaged PCM terminals before replacing PCM.