LEMON Manuals: Even more car manuals for everyone
Home >> GMC >> 1986 >> Safari Van M V6-262 4.3L >> Repair and Diagnosis >> A L L Diagnostic Trouble Codes ( DTC ) >> Testing and Inspection >> Manufacturer Code Charts >> DTC 33

DTC 33

Code 33 - MAP Sensor (Voltage High):




Wiring Diagram For Code 33 - MAP Sensor:






CODE 33 - MAP SENSOR (SIGNAL VOLTAGE HIGH)


Circuit Description:

The Manifold Absolute Pressure Sensor (MAP) responds to changes in manifold pressure (vacuum). The ECM receives this information as a signal voltage that will vary from about 1 to 1.5 volts at idle to 4 - 4.5 volts at wide open throttle.

If the MAP sensor fails the ECM will substitute a fixed MAP value and use the Throttle Position Sensor (TPS) to control fuel delivery.

Code 33 will set when:

^ Signal is too high for a time greater than 5 seconds
^ TPS voltage indicates throttle is closed.
^ Vehicle speed is "0" MPH.

Engine misfire or a low unstable idle may set Code 33. Disconnect MAP sensor and system will go into backup mode. If the misfire or idle condition remains, See Diagnosis By Symptoms - No Trouble Codes Stored.



Test Description:

1. Confirms Code 33 if that fault is still present



2. If the ECM recognizes and sets Code 34, low MAP signal, the ECM and wiring are OK.