P0108 — Manifold Absolute Pressure/Barometric Pressure Circuit High Input
Drive with caution — fix soon.
What P0108 means
This code means the manifold absolute pressure (MAP) sensor circuit is sending a signal that's too high, often from a wiring short to power, a disconnected vacuum hose, or a failed sensor. The computer then over-fuels the engine, hurting economy and emissions. It's a common code and is usually fixable by repairing wiring, fixing the vacuum connection, or replacing the sensor.
Common symptoms
- Check engine light is on
- Rough idle or engine shaking
- Hesitation or sluggish acceleration
- Poor fuel economy and rich-running engine
- Black smoke or strong fuel smell from exhaust
Common causes
- Wiring short to power in the MAP sensor circuit
- Disconnected or leaking vacuum hose to the sensor
- Failed MAP sensor
- Corroded or damaged connector
- Restricted or blocked intake passage
Typical repair cost
$100 – $350
Varies by vehicle and root cause.
Frequently asked questions
Can I keep driving with a P0108 code?
For short trips, usually yes, but the engine may run rich, idle rough, and waste fuel. Since the sensor reads too high, the computer over-fuels the engine. Have it diagnosed soon.
How much does it cost to fix a P0108?
Most repairs run $100 to $350. A wiring or vacuum hose fix is cheaper, while a new MAP sensor with labor sits toward the higher end.
Is a P0108 code serious?
It's moderate. It won't usually cause immediate engine damage, but running rich for a long time wastes fuel and can foul spark plugs or harm the catalytic converter, so don't leave it too long.
What causes a P0108 high input?
A high signal usually comes from the circuit shorting to power, a disconnected vacuum hose, or a failed sensor. A mechanic checks the vacuum connection and wiring before deciding whether the sensor needs replacing.