Check the MAF for contamination, deterioration, or damage.

Is the MAF contaminated, deteriorated or damaged?

YES

▶ Repair or replace as necessary and Go to "Verification of Vehicle Repair" procedure.

NO

▶ Go to " Check MAF" as below.

Engine "ON"

Connect Scantool and select the "MAF SENSOR" parameter on the CURRENT DATA.

Monitor signal waveform of the "MAF SENSOR" on the Scantool.

Specification : Check that MAF value is increased correspondently with TPS when pressing accelerator pedal.

Is the measured signal waveform of MAF sensor displaying correctly ?

YES

▶ Go to "Check PCM" as below.

NO

▶ Substitute with a known - good MAF and check for proper operation.

▶ If the problem is corrected, replace MAF and go to "Verification of Vehicle Repair" procedure.

Ignition "OFF"

Connect Scantool and Ignition "ON"

Select simulation function on scantool.

Simulate voltage at terminal 1 of MAF sensor signal connector.

Does the signal value of MAF sensor changes according to simulation voltage ?

YES

▶ Thoroughly check connectors for looseness, poor connection, bending, corrosion, contamination, deterioration, or damage. Repair or replace as necessary and go to "Verification of Vehicle Repair" procedure.

NO

▶ Substitute with a known - good PCM and check for proper operation.

If the problem is corrected, replace PCM and go to "Verification of Vehicle Repair" procedure.