Diagnostic Aids
An intermittent may be caused by a poor connection, mis-routed harness, rubbed through wire insulation or a wire broken inside the insulation. Check for:
- Poor Connection At PCM pin: Inspect harness connectors for backed out terminals, improper mating, broken locks, improperly formed or damaged terminals, and poor terminal to wire connection.
- Mis-Routed Harness: Inspect MAF sensor harness to ensure it is not too close to high voltage wires, such as spark plug wires.
- Damaged Harness: Inspect harness for damage. If harness appears okay, observe Tech-1 while moving related connectors and wiring harness. A change in display would indicate intermittent fault location.
- Plugged Air Intake Filter: A wide-open throttle acceleration from a stop should cause MAF reading on Tech-1 to range from approximately 4-7 grams per second at idle to 100 or greater at time of 1-2 shift. If not, check for restriction.