Manifold Absolute Pressure/Barometric Pressure Circuit Malfunction
Common Symptoms
- Check Engine Light illuminated
- Rough idle or engine stalling
- Poor fuel economy
- Lack of power during acceleration
- Hard starting or extended cranking
- Black smoke from exhaust under load
Most Likely Root Causes
- Faulty MAP sensor
- Damaged or corroded wiring harness to MAP sensor
- Vacuum leak at intake manifold or sensor vacuum line
- Poor electrical connection at MAP sensor connector
- Failed Engine Control Module
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Component Location
The MAP sensor is typically mounted on the intake manifold or connected via a vacuum hose to the intake manifold.
Manufacturer Notes
Some manufacturers use integrated MAP/IAT sensors which require replacement as a complete assembly when the MAP circuit fails.
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