With TBI

Fig. 056 - Wiring Diagram for Code 34 MAP Sensor. VIN 0, VIN 2, VIN R, VIN U:

CODE 34,

MAP SENSOR (SIGNAL VOLTAGE LOW)

1.8L "J" SERIES

2.5L "A, X, & N" SERIES

FUEL INJECTION (TBI)

Fig. 055 Chart - Code 34 MAP Sensor (Signal Voltage Too 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 1.5 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 Postion Sensor (TPS) to control fuel delivery.
Code 34 will set when signal is to low and ignition is turned on.
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.