OBD-II Diagnostic Trouble Code
P0106 — Manifold Absolute Pressure/Barometric Pressure Circuit Range/Performance
P0106 means the MAP or barometric pressure reading is electrically valid but does not make sense for engine conditions. The ECM compares it to baro at key-on, throttle or pedal position, rpm and, on some engines, turbo speed, and the values did not agree. On diesels this usually involves the boost pressure sensor and real boost problems.
Severity 3/5
Truck-relevant
Service this week
Severity
Service this week
Manifold Absolute Pressure/Barometric Pressure Circuit Range/Performance
Code
P0106
Category
Powertrain
Subsystem
Air Flow
Truck-relevant
Yes
What this means for truckers
Service within a few days on a Cummins X15, Detroit DD15, PACCAR MX-13. Performance is likely degraded. Continuing to drive without service risks additional component damage.
Before you replace parts — try this first
P0106 on the Air Flow system is most often plugged, cracked or oil-fouled sensor port or hose — not a dead part. On commercial diesels especially, work these in order before spending money on parts:
- Confirm the symptoms. Match what your truck is doing to the Symptoms section below. If the code is set but the symptoms are not there, clear the code and re-test after a drive cycle — it may not return.
- Clean and dry the sensor connector. Water, road salt, or oil seeping into a connector is the #1 fake sensor failure. Disconnect, look for green corrosion or moisture, spray with electrical contact cleaner, dry, reseat. Many faults clear here for $0.
- Inspect the wiring harness. Trace the wire from the sensor toward the ECM — look for chafing against the engine block, melted insulation near the turbo or exhaust, or pinch points where a clamp has rubbed through.
- Test the sensor before swapping it. Most Common Causes (below) list the expected voltage or resistance range — a $20 multimeter saves a $300 sensor swap that does not fix the problem.
- Only then, replace the part. Use the OEM or a tier-1 aftermarket. Cheap sensors throw the same code in two weeks.
Symptoms
Low power, derate, slow turbo response, black smoke, or poor fuel economy. Gas engines may idle rough. Often appears with turbo underboost/overboost, EGR or charge air cooler codes.
Common causes
- CommonPlugged, cracked or oil-fouled sensor port or hose ($30–$200)
- CommonBoost leak in the charge air cooler, piping or clamps ($80–$1500)
- OccasionalSkewed MAP/boost sensor ($120–$400)
- OccasionalTurbo actuator, VGT or wastegate problem giving abnormal boost ($500–$3500)
- OccasionalIntake vacuum leak on gas engines ($50–$300)
How to fix
Compare key-on, engine-off MAP and baro readings to each other and to local baro
When to use: First check to catch a skewed sensor
Clean the sensor port and inspect sensor sealing and any hose
When to use: When readings are sluggish or offset, especially on engines with oily intake
Pressure test the charge air system and check turbo actuator operation
When to use: When the sensor reads correctly at key-on but boost is low under load
Replace the MAP/boost sensor
When to use: When the reading is off at key-on or does not track a known-good gauge
Affects most
No specific vehicle pattern found in our complaint database. This code can appear on any vehicle that supports OBD-II diagnostics.
Related
- → Browse all DTC trouble codes
- → Decode a VIN to check codes for your truck
- → Owner-operator maintenance guides
- → P0100 — Mass or Volume Air Flow Circuit
- → P0101 — Mass or Volume Air Flow Circuit Range/Performance
- → P0102 — Mass or Volume Air Flow Circuit Low Input
- → P0103 — Mass or Volume Air Flow Circuit High Input
- → P0104 — Mass or Volume Air Flow Circuit Intermittent
Frequently Asked Questions
Can I drive with code P0106?
P0106 is severity 3 — plan service within a few days. Performance is likely degraded already (you may feel reduced power, harsher shifts, or slightly worse fuel economy). Continuing to drive risks additional damage to adjacent components.
How much does it cost to fix P0106 on a commercial truck?
Total repair cost ranges $30–$3500 depending on the root cause. The cheapest fix is usually the first one listed below — Plugged, cracked or oil-fouled sensor port or hose — which is also the most common. On commercial trucks the cost is usually higher than passenger vehicles due to part availability and shop labor rates ($120–185/hour at most truck shops, vs $90–130 at general auto shops). DIY-capable fixes (sensors, hoses, filters) are at the low end; major component replacements (turbo actuator, high-pressure fuel pump, transmission solenoid pack) are at the high end. Always diagnose with a scan tool BEFORE replacing parts — guessing wrong on a $1,500 turbo actuator when the actual issue was a $30 boost hose is a common expensive mistake.
Will P0106 fail a DOT inspection?
P0106 is generally not a direct DOT inspection fail item by itself. Inspectors focus on safety-critical systems (brakes, steering, tires, lights, hours-of-service). However, the check engine light alone can trigger additional inspection scrutiny. Best practice: fix the code and clear it before a planned inspection.
What's the difference between P0106 and related codes?
P0106 is closely related to: P0100 (Mass or Volume Air Flow Circuit), P0101 (Mass or Volume Air Flow Circuit Range/Performance), P0102 (Mass or Volume Air Flow Circuit Low Input), P0103 (Mass or Volume Air Flow Circuit High Input). These codes share the same subsystem (air-flow) and often appear together. If you see this code, scan for the full code list — fixing the root cause usually clears multiple companion codes at once. If only P0106 is set without the companions, the issue is more isolated.
How do I prevent P0106 from coming back after a repair?
For P0106 (Manifold Absolute Pressure/Barometric Pressure Circuit Range/Performance), prevention centers on the air flow system. Service air filter on time. Clean MAF sensor at every air filter change. Inspect intake boots/hoses for cracks — vibration kills them eventually.