P0107
Manifold Absolute Pressure/Barometric Pressure Circuit Low InputP0107 is a generic OBD-II powertrain diagnostic trouble code: Manifold Absolute Pressure/Barometric Pressure Circuit Low Input. It is logged by the engine control unit when the air/maf monitor detects that a specific fault threshold has been exceeded — typically resulting in the malfunction-indicator lamp (MIL / check-engine light) being illuminated.
What P0107 means
P0107 is set when the ECM/PCM detects a voltage signal from the Manifold Absolute Pressure (MAP) sensor that falls at or below approximately 0.2 V — well outside the normal operating range of roughly 1 V at idle up to 4.5 V at wide-open throttle. A signal this low typically indicates an open circuit, a short to ground in the signal wire, or a failed sensor that can no longer produce a valid output. The MAP sensor measures intake manifold vacuum so the ECM can calculate engine load and adjust fuelling and ignition timing accordingly.
With no reliable pressure signal, the ECM cannot correctly determine how much air is entering the engine. It will usually substitute a fixed default value or fall back on barometric pressure, which causes the engine to run with an excessively rich air-fuel mixture. This manifests as black exhaust smoke, poor fuel economy, a rough or unstable idle, hesitation under acceleration, and in some cases a hard start or stall. A vacuum leak between the sensor port and the intake manifold can also drag the signal low without an electrical fault.
Because MAP data is central to fuelling decisions, most vehicles illuminate the MIL immediately and some enter a reduced-power or limp mode. Diagnosing the fault in order — vacuum lines first, then wiring and connector integrity, then sensor reference voltage, and finally the sensor itself — prevents unnecessary parts replacement.
Common causes
Most-frequently reported root causes when P0107 is logged.
-
1
Defective MAP sensor with an internal electrical failure causing the output to drop below 0.2 V.
-
2
Signal wire shorted to ground or to chassis metal, pulling the voltage to near zero.
-
3
Open circuit in the sensor signal wire due to a broken, corroded, or chafed harness.
-
4
Corroded, bent, or poorly seated connector pins at the MAP sensor plug.
-
5
Split, kinked, disconnected, or collapsed vacuum hose between the sensor and intake manifold.
-
6
Intake manifold vacuum leak that causes an abnormally low pressure reading.
-
7
Water or oil contamination inside the sensor port or connector affecting electrical output.
-
8
Faulty PCM/ECM (rare — rule out all wiring and sensor causes first).
Symptoms drivers notice
How to diagnose P0107
A typical diagnostic flow when this code is present.
-
1
Connect an OBD-II scanner, record freeze-frame data, and note any additional related codes (e.g. P0108, P0171, P0172).
-
2
Inspect the vacuum hose from the MAP sensor port to the intake manifold for cracks, kinks, disconnections, or softening — repair or replace as needed.
-
3
Visually inspect the MAP sensor wiring harness and connector for chafing, corrosion, bent pins, or loose fitment; repair any damage found.
-
4
With ignition on (engine off), back-probe the sensor connector and confirm 5 V on the reference pin and good ground on the ground pin using a multimeter.
-
5
Check the signal pin voltage: at key-on with a good vacuum reference you should see roughly 1.5–2.5 V; a reading below 0.2 V confirms a low-signal fault in the circuit.
-
6
Disconnect the sensor, connect a known-good MAP sensor or a sensor simulator, and recheck signal voltage to isolate whether the fault is in the sensor or the wiring.
-
7
If wiring and sensor test good, check for intake vacuum leaks using a smoke machine before suspecting PCM/ECM failure.
Related powertrain codes
- P0068 — MAP/MAF - Throttle Position Correlation
- P006A — MAP - Mass or Volume Air Flow Correlation Bank 1
- P00B8 — MAP - Mass or Volume Air Flow Correlation Bank 2
- P00BC — Mass or Volume Air Flow A Circuit Range/Performance - Air Flow Too Low
- P00BD — Mass or Volume Air Flow A Circuit Range/Performance - Air Flow Too High
- P00BE — Mass or Volume Air Flow B Circuit Range/Performance - Air Flow Too Low
Frequently asked questions
Can I drive with a P0107 code?
Short trips at low load may be possible, but the rich mixture and potential limp mode mean you risk poor driveability, fouled spark plugs, and catalyst damage. Repair it promptly.
What voltage should the MAP sensor signal show at idle?
Typically around 1.0–1.5 V at a warmed idle (higher vacuum = lower pressure = lower voltage). Wide-open throttle approaches 4.5 V. A reading at or below 0.2 V is abnormal and triggers P0107.
Could a vacuum leak cause P0107?
Yes. A large vacuum leak lowers manifold pressure enough that the MAP signal may drop below the ECM's minimum plausibility threshold, setting the code even when the sensor and wiring are intact.
P0107 and P0108 appeared together — what does that mean?
Simultaneous high and low codes often point to an intermittent wiring fault (loose connector, broken wire) that swings the signal between extremes rather than a sensor that is simply stuck low or high.
Disabling P0107 in software
RaceTune can permanently disable P0107 — and any other OBD-II diagnostic trouble code — on every ECU family we support. The monitor is disabled inside the ECU itself, so the fault stops being logged: the warning light stays off and the engine never enters limp mode for this code. The change is tied to your exact software version.
Software modifications affect emissions compliance and are not road-legal in many jurisdictions. RaceTune service files are intended for motorsport, off-road, and export use.
Got P0107 in your scan?
Upload your ECU file — we'll identify the exact software version and confirm whether a disable is available for your car.
Upload your file