MAP Sensor Circuit Intermittent Low Voltage (GM)
What does P1107 mean?
The P1107 code means the vehicle's onboard diagnostic system has detected: MAP Sensor Circuit Intermittent Low Voltage (GM). This is a moderate severity code.
Common Symptoms
- Check Engine Light on
- Engine surging at idle
- Lack of power during acceleration
- Poor fuel economy
- Engine stalling
Probable Causes (Ranked by Likelihood)
- Faulty MAP sensor Very High
- Corroded or loose MAP sensor electrical connector High
- Open circuit in MAP sensor signal wire Moderate
- Damaged MAP sensor ground circuit Moderate
- PCM internal failure Low
Step-by-Step Diagnostic Procedure
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Use a scan tool to read MAP sensor voltage at key-on engine-off (should read about 4.5V)
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Inspect the MAP sensor connector for water intrusion, corrosion, or spread terminals
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Check for vacuum leaks that may affect MAP sensor readings
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Perform a wiggle test on the MAP sensor wiring while monitoring voltage
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Test the 5V reference and ground circuits at the MAP sensor connector
Frequently Asked Questions
What does P1107 mean on a GM vehicle?
P1107 indicates the MAP sensor is intermittently sending a lower-than-expected voltage signal to the PCM. This causes incorrect fuel metering and ignition timing.
Can a vacuum leak cause P1107?
Yes, a vacuum leak can cause incorrect MAP sensor readings that may trigger this code. Check all vacuum hoses and the intake manifold gasket for leaks.
Is P1107 serious?
It is moderately serious. While you can drive short distances, the engine may stall or lack power. Repair should be addressed within a week to prevent poor fuel economy and potential catalytic converter damage.