P1297

Tests 488 - 493:

Tests 494 - 496:

SYMPTOM
P-1297 NO CHANGE IN MAP FROM START TO RUN

WHEN MONITORED
With engine rpm above 400 but less than 1500 and the throttle body at closed throttle.

SET CONDITION
Too small a difference is seen between barometric pressure at ignition on and manifold vacuum (engine running) for 8.8 seconds.

POSSIBLE CAUSES
- MAP sensor 5-volt supply circuit open
- MAP sensor wiring harness intermittent defect
- Vacuum ports restricted or def
- MAP sensor def (press change)
- MAP sensor def (no press change)
- MAP sensor restricted