DF9

- Key "OFF".

- Plug Manifold Absolute Pressure (MAP) sensor vacuum supply hose.

- Start engine and maintain 1500±100 engine rpm.

- Slowly apply 51 kPa (15 in Hg) vacuum to MAP sensor.

- While maintaining rpm, perform Key On Engine Running (KOER) Self-Test. Key ON Engine Running (KOER) Self-Test

- Is KOER Diagnostic Trouble Code (DTC) 126 still present?

NOTE: Disregard any other DTCs at this time.

Yes -- Replace MAP sensor. Connect vacuum supply hose to MAP sensor. Rerun quick test. Quick Test Appendix (Detailed Testing Instructions)

No -- Inspect vacuum supply hose to MAP sensor. Service as necessary.

If OK, service other KOER DTCs. Manufacturer Code Charts

If none, return to Diagnosis by Symptom (Diagnostic Routines) to address any drive concerns.