P0109: Manifold Absolute Pressure/Barometric Pressure Sensor Circuit Intermittent
What to do
May drive normally much of the time with occasional roughness. Mention that the fault is intermittent.
What this code means
The manifold pressure signal is unstable rather than steadily wrong. As with any intermittent sensor code, the harness and connector deserve suspicion ahead of the sensor. A vacuum hose that is cracked rather than split will also produce an unstable reading that changes with engine movement and temperature.
Likely causes
Start here
- Intermittent wiring fault · moderate
- Corroded or loose connector · easy
- Blocked or split MAP sensor vacuum hose · easy
Less common
Symptoms
Components involved
Information, not instruction
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Community experience
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