Mike's Workshop Manuals: Service manuals for every vehicle
Home >> Cadillac >> 1992 >> DeVille Touring >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Tests W/Codes >> Pcm Trouble Code Diagnosis >> Pcm Code E34, Map Signal Too High >> Action

Pcm Code E34, Map Signal Too High: Action

PCM turns on SERVICE ENGINE SOON light. PCM sets BARO at 92 kPa and substitutes MAP sensor values based on engine RPM and throttle switch status.

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 on altitude.
  2. Check for vacuum at MAP sensor hose using vacuum gauge. At idle, typical vacuum readings are 14-20 in. Hg depending on engine load.
  3. Checks for faulty MAP sensor or MAP circuitry.
  4. Checks for sensor ground open from sensor to PCM.
  5. Checks for short to voltage on sensor signal circuit No. 432.
  6. Fault is most likely at PCM connector or PCM. Before PCM is replaced, perform PFI CHART C-1, PCM REPLACEMENT CHECK.