DTC 34

Fig. 010 - Wiring Diagram for Code 34 MAP Sensor (Signal Voltage Too High):

CODE 34, MAP SENSOR (SIGNAL VOLTAGE LOW)

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 1-1/2 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 34 will set when signal is too low when ignition is turned on.

Fig. 009 - Chart Code 34 MAP Sensor (Signal Voltage Too Low):

1. Confirms Code 34, and that fault is present.
2. If the ECM recognizes and sets Code 33, high MAP signal, the ECM and wiring are OK.