P0109
PowertrainFuel Air Meteringmoderate severityMAP/BARO Pressure Circuit Intermittent
What P0109 Means
The MAP sensor signal is showing intermittent readings.
Symptoms
- Check Engine Light (intermittent)
- Erratic idle
- Stumble on acceleration
Common Causes
- Loose connector
- Damaged wiring
- Intermittent vacuum leak
Diagnostic Steps
- Wiggle test on connector
- Monitor MAP signal
- Check vacuum hose
Where to start: Repair connector or wiring.
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