Code 33 - Map Sensor Signal Volt Hi (A/F/J/N/P Body)

The Manifold Absolute Pressure (MAP) sensor responds to changes in manifold pressure (vacuum). The ECM receives this information as a signal voltage that will vary from about 1-1.5 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 TPS to control fuel delivery.

Code 33 will set when signal reading is too high for a time greater than 8 seconds and if the TPS voltage indicates throttle is closed. Engine misfire or a low and unstable idle may set Code 33. Disconnect MAP sensor and system will go to backup mode. If misfire or idle condition remains, refer to the CCC TESTS W/O CODES article in this section.

1. This test confirms Code 33, and that fault is present.
2. If the ECM recognizes and sets Code 34, low MAP signal, the ECM and wiring are okay.

Fig 1: Code 33 Flow Chart: MAP Sensor Signal Voltage High

Fig 2: Code 33 Flow Chart: MAP Sensor Signal Voltage High

Fig 3: Code 33 Schematic: MAP Sensor Signal Voltage High