P0106
Manifold Absolute Pressure/Barometric Pressure Circuit Range/Performance ProblemP0106 is a generic OBD-II powertrain diagnostic trouble code: Manifold Absolute Pressure/Barometric Pressure Circuit Range/Performance Problem. 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 P0106 means
P0106 is a rationality fault, not a simple voltage out-of-range code. It means the MAP (manifold absolute pressure) sensor is producing a signal that falls within valid electrical bounds — its voltage is neither too high nor too low — but the pressure value it reports does not match what the ECM expects given the engine's current operating state. The ECM cross-checks MAP output against throttle position, engine speed, mass air flow (where fitted), and barometric pressure; when those inputs disagree beyond a calibrated tolerance, P0106 is logged. Out-of-range voltage faults trigger P0107 (too low) or P0108 (too high) instead.
Typical failure modes involve a vacuum leak that raises manifold pressure above what the throttle angle and engine load should produce, a contaminated or degraded MAP sensor whose pressure-to-voltage transfer function has shifted, or a blocked vacuum hose connecting the sensor port to the manifold. On turbocharged engines, a leaking boost pipe or intercooler connection can also cause the manifold pressure to deviate from expected values at higher loads.
Symptoms range from rough idle and hesitation to reduced fuel economy, as the ECM either defaults to a substitute pressure value or bases injection timing and quantity on incorrect sensor data. On some calibrations the fault triggers a failsafe mode that limits boost or throttle authority.
Common causes
Most-frequently reported root causes when P0106 is logged.
-
1
Vacuum leak in the intake manifold or between the MAP sensor port and manifold bung, raising measured pressure above expected values.
-
2
Cracked or disconnected vacuum hose connecting the MAP sensor to the intake manifold.
-
3
Contaminated or shifted MAP sensor calibration — sensor voltage is in range but the pressure reading is inaccurate.
-
4
Blocked MAP sensor port due to carbon deposits or oil vapour accumulation.
-
5
Faulty throttle position sensor providing an incorrect load reference that makes the MAP value appear irrational.
-
6
Leaking intake manifold gasket altering pressure characteristics seen by the sensor.
-
7
On turbocharged engines: leaking intercooler pipe or boost pipe causing manifold pressure inconsistency under load.
-
8
PCM software fault or corrupted calibration tables (rare, typically only after a failed reflash).
Symptoms drivers notice
How to diagnose P0106
A typical diagnostic flow when this code is present.
-
1
Record freeze frame and all co-stored codes — P0068 (MAP/MAF/throttle correlation) or throttle position codes alongside P0106 help narrow the root cause.
-
2
With the engine off, use a scan tool to compare the MAP sensor reading to barometric pressure (BARO); they should match within a few kPa — a large discrepancy with no vacuum applied indicates a sensor or port fault.
-
3
Inspect the MAP sensor vacuum hose and manifold port for cracks, oil fouling, or disconnection.
-
4
Perform a smoke test on the intake system to detect vacuum leaks that would artificially elevate manifold pressure.
-
5
Start the engine and monitor MAP, throttle position, and (if available) MAF live data simultaneously; at idle, MAP should read significantly below BARO (typically 25–45 kPa on a naturally-aspirated engine), and should rise smoothly to near-BARO at wide-open throttle.
-
6
Clean the MAP sensor port and hose with carb/throttle body cleaner if oil or carbon contamination is found.
-
7
If all vacuum and intake checks pass and live data shows the MAP reading is inconsistent with throttle and RPM, replace the MAP sensor and retest.
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
Why is P0106 a rationality fault rather than a voltage fault?
The ECM validates sensor inputs against each other, not just against electrical limits. P0107 and P0108 fire when the MAP voltage itself is below 0.1 V or above 4.9 V — obviously out of range. P0106 fires when the voltage is electrically plausible but the pressure value it represents is inconsistent with what the throttle position, RPM, and MAF sensor predict it should be. A sensor that has shifted its calibration can pass voltage checks completely and still trigger P0106.
Can a vacuum leak cause P0106?
Yes, and it is one of the most common causes. A vacuum leak raises manifold pressure above what the throttle angle and engine speed would normally produce. The ECM sees a MAP value that is too high relative to the other inputs and sets P0106. A smoke test on the intake system is the most reliable way to find small leaks.
How do I test the MAP sensor without replacing it?
With the ignition on and engine off, use a scan tool to read the MAP value — it should match atmospheric (BARO) pressure closely. Then start the engine; at idle the reading should drop significantly (25–45 kPa typical on a naturally-aspirated engine). Snap the throttle and the reading should rise quickly back toward BARO. A sensor that stays at an unexpected fixed value or moves erratically is defective.
Is P0106 the same fault on a turbocharged engine as on a naturally-aspirated one?
The code definition is the same, but on a turbocharged engine the expected MAP range extends above atmospheric pressure under boost. P0106 on a turbo engine more often points to a leaking intercooler pipe or boost hose, a faulty recirculation valve, or a MAP sensor that cannot accurately track rapid pressure changes under load.
Disabling P0106 in software
RaceTune can permanently disable P0106 — 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 P0106 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