P0107: The MAP sensor voltage is too low
Manifold Absolute Pressure/Barometric Pressure Circuit Low Input
The manifold pressure (MAP) sensor signal is too low, so the engine may run lean under load. Get it checked within a few days. If it runs rough, loses power or the temperature gauge climbs, stop driving.
Stop driving and get help if
- The check engine light is flashing
- The temperature gauge runs high, or you see steam (overheating)
- The car loses power, hesitates badly or stalls
- You smell burning or see smoke
- A brake warning light comes on, or the brakes feel different
Pull over as soon as you can, turn the engine off, and call a tow or roadside help.
What it means
The MAP sensor signal has dropped below the minimum acceptable voltage. Below this threshold the computer rejects the reading entirely and runs in a fallback mode. Low MAP voltage almost always means a power or ground problem at the sensor, a broken wire in the signal circuit, or a sensor that has internally shorted to ground. Unlike P0106, which is a range issue, P0107 is a hard electrical fault.
Common causes
- Failed MAP sensor shorted internallyAn internal short pulls the signal line toward ground, giving near-zero voltage output.
- Broken signal wire or ground wireA single cut or corroded wire in the MAP harness drops the signal below threshold.
- Corroded or damaged connectorMoisture in the connector corrodes pins and breaks the signal path.
- Short to ground in the wiringA chafed wire touching the chassis pulls the MAP signal down the same way a failed sensor would.
What the fix could involve
From the cheaper fix to the bigger one. Prices depend on your car, your area and the shop, so ask for a written quote that names the part and the labor before you approve it.
- MAP sensor replacement
- Wiring or connector repair
Symptoms
- Check engine light on
- Very lean idle and acceleration
- Stalling, especially at low loads
- Hesitation when pressing the accelerator
- RPM hunting at idle
What to do next
Check the MAP sensor connector for moisture and corrosion. With a multimeter and the ignition on, confirm the sensor has 5V reference voltage on one pin and a clean ground on another. If the reference is good but the output reads below 0.5V, the sensor is likely shorted internally and needs replacement. If reference voltage is missing, trace the power circuit from the ECM.
Lewis reads P0107 alongside any related MAP and sensor reference codes, so you can see whether one sensor or a shared circuit is the more likely fault. Get Lewis on the App Store or Google Play.
Related codes
FAQ
- Can a MAP sensor read 0 volts and still run the engine?
- The ECM will enter a limp-home mode and use estimated values for manifold pressure. The engine will run poorly but usually will not shut off immediately.
- I replaced the MAP sensor and P0107 came back. What else can cause this?
- A short to ground in the wiring harness between the sensor and the ECM will pull down any sensor you install. Trace the wiring for damage before replacing a second sensor.
- Is P0107 dangerous to drive with?
- It is risky under load. The lean condition from an underreported manifold pressure can cause detonation on hard acceleration. Get it checked within a few days and avoid hard acceleration until then.
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