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Home >> Saturn >> 1992 >> SC Standard >> Repair and Diagnosis >> External Pages >> Different car >> Section 10 (Engine Controls - Tests W/Codes - 4.9L) >> Pcm Code Charts >> Code P034, Map Sensor Signal Too High >> Action
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Code P034, Map Sensor Signal Too High: Action

WARNING: This page is about a different car, the 1995 Cadillac DeVille. However, it is still accessible from the selected car via links, so may be relevant.

PCM turns on MIL and 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.
  1. MAP at idle should be 30-50 kPa, depending on engine load. BARO should be 85-105 kPa, depending upon altitude.
  2. Check for vacuum at fuel pressure regulator hose. At idle, typical vacuum reading should be 14-20 in. Hg, depending on engine load.
  3. Checks for MAP sensor or MAP circuit faults.
  4. Checks if sensor ground is open from sensor to PCM.
  5. Checks for short to voltage on circuit No. 432.
  6. Fault is most likely at PCM connector or PCM. Before replacing PCM, check for damaged pins or poor connections.