P0108: Manifold Absolute Pressure/Barometric Pressure Sensor Circuit High
What to do
Expect rich running and poor economy. Have the sensor's vacuum hose checked first; a hose off its spigot is a common and cheap find.
What this code means
The manifold pressure signal is above its valid range — a short to supply, or an open signal wire floating high. High manifold pressure reads as high load, so the module adds fuel and the engine runs rich. A disconnected vacuum hose to the sensor produces the same reading as atmospheric pressure, which at idle is high enough to set this code without anything electrical being wrong at all.
Likely causes
Start here
- Blocked or split MAP sensor vacuum hose · easy
- Wiring shorted to voltage · moderate
- Faulty manifold absolute pressure sensor · easy
Less common
- Open circuit in sensor wiring · moderate
- Corroded or loose connector · easy
Symptoms
Components involved
Information, not instruction
CarGeek is a reference, not a service manual. Its pages are written from public sources and from what other people have found, never from a manufacturer's own service information, so they can be wrong or incomplete for your particular vehicle. Some of what they describe carries real risk: high voltage, fuel under pressure, stored energy, hot and moving parts.
Have anything you intend to act on checked by a trained person against the manufacturer's own procedure for your vehicle. Nothing here replaces that procedure.
Community experience
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