Common Symptoms
- Check Engine Light illuminated
- Poor fuel economy
- Reduced engine power or hesitation
- Hard starting in high altitude conditions
- Black smoke from exhaust under acceleration
- Engine runs rich or lean intermittently
Most Likely Root Causes
- Faulty barometric pressure sensor
- Contaminated or damaged MAP sensor (when BARO is calculated)
- Intermittent wiring or connector issues to pressure sensor
- ECM software calibration outdated
- Restricted air intake or filter causing incorrect readings
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Component Location
Barometric pressure sensor is typically integrated into the MAP sensor on the intake manifold or mounted separately on the engine compartment firewall.
Manufacturer Notes
Many modern ECMs calculate barometric pressure from MAP sensor data during key-on or wide-open-throttle conditions rather than using a dedicated sensor.
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