Diesel Data: Automotive Repair

DTC 33

Fig. 016 - WIRING DIAGRAM FOR Code 33 Mass Air Flow Sensor. VIN 3, VIN 9:





CODE 33

MASS AIR FLOW (MAF) SENSOR

3.8L "A" & "C" SERIES

3.8L TURBO "E" & "G" SERIES

FUEL INJECTION (PORT)

The MAF Sensor measures the flow of air entering the engine. This information is used by the ECM for fuel control.
Code 33 will set when:
a. Engine is idling
b. TPS is 10% or less
c. Air Flow more than 150 grams per second (high frequency).
d. All of the above are met for 5 seconds or more.


Fig. 014 - Chart - Code 33 Mass Air Flow Sensor (Signal Frequency High):





1. Checks to see if the ECM recognizes a problem.
2. Inspect wire routing of high voltage wires such as spark plug wires. Such wires routed too closely to MAF wiring harness could possibly cause an intermittent Code 33.