# P0106: Manifold Absolute Pressure/Barometric Pressure Circuit Range/Performance **Verdict:** Drive to a shop this week Air intake - Generic OBD-II code, applies to all gasoline cars and light trucks sold in the US since 1996. - **Typical cost:** $50-$600 - **Urgency:** This week - **Most likely:** Cracked MAP hose or failing MAP sensor - **DIY?:** Yes, steps 1-3 ## Quick answer P0106 means the reading from the manifold absolute pressure (MAP) sensor does not make sense compared with what the engine computer expects from throttle position, engine speed and other sensors. The circuit is working, but the values are implausible. A cracked or loose vacuum hose, a vacuum leak or a failing MAP sensor are the usual causes. ## What does P0106 mean? The MAP sensor measures pressure inside the intake manifold. With the key on and the engine off, manifold pressure equals outside air pressure, so many computers use that moment to learn barometric pressure, which is why the title also says BARO. Once the engine runs, manifold pressure drops as the throttle closes and rises toward outside pressure under heavy load. The computer uses it to judge engine load and set fuel and spark. P0106 is a range or performance code, not a wiring fault. The computer compares MAP readings with what they should be for the throttle opening and RPM, with the MAF sensor where one is fitted, and with the baro reading at key-on. If MAP stays too high, too low or too steady for the conditions, it sets the code, often after two trips. Circuit faults use P0107 and P0108 instead. ## What are the symptoms of P0106? - Check engine light on - Rough idle or stalling - Hesitation or flat spots when accelerating - Worse fuel economy - Black smoke or a fuel smell on some engines ## What causes P0106? Ranked from most to least likely. Check them in this order: the cheap, common causes first. 1. **Cracked, loose or plugged MAP vacuum hose** (most common). On engines where the MAP sensor connects to the manifold through a rubber hose, the hose can crack, collapse, come loose or fill with oil or fuel residue. The sensor then reads pressure that lags or does not match real manifold pressure. Heat and age harden these hoses. Sensors mounted directly on the manifold can have a dried-out O-ring instead. 2. **Failing or contaminated MAP sensor** (common). MAP sensors can drift or respond slowly with age, heat or oil vapor from the PCV system, without failing completely. The reading then looks plausible at idle but falls behind the throttle. Comparing key-on MAP with known barometric pressure, and watching how it responds to a quick throttle snap, often exposes a lazy sensor. 3. **Vacuum or intake leak** (common). A large leak at the intake gasket, PCV system, brake booster or throttle body gasket raises manifold pressure at idle above what the computer expects with the throttle closed. Lean fuel trim codes such as P0171 often appear too. A smoke test of the intake finds leaks that are too small to hear. 4. **Engine problem lowering intake vacuum** (less common). A healthy engine pulls strong, steady vacuum at idle. Valve timing that is off, a restricted exhaust such as a clogged catalytic converter, or low compression can weaken vacuum so MAP reads high even though the sensor is fine. A vacuum gauge on the manifold quickly shows whether the engine or the sensor is at fault. 5. **Intermittent wiring or connector fault** (rare). A loose terminal, corrosion or a chafed wire can make the signal jump or drift without falling far enough to set P0107 or P0108. The fault may come and go with engine vibration or heat. Wiggling the harness while watching live MAP data, and checking the 5-volt reference and ground, often finds it. ## How do you diagnose P0106? 1. With the key on and engine off, compare the MAP reading with local barometric pressure; they should be close. 2. At warm idle, check that MAP drops well below barometric pressure and rises quickly when you snap the throttle. 3. Inspect the MAP hose or O-ring and the intake for cracks, looseness or oil, and smoke-test for leaks. 4. Connect a vacuum gauge to confirm the engine itself makes normal, steady vacuum. 5. Check the 5-volt reference, ground and signal wires for drops or intermittent changes. ## How do you fix P0106, and what does it cost? | Fix | Typical cost | What it involves | | --- | --- | --- | | Replace MAP vacuum hose or sensor O-ring | $50-$150 | Cheap and common; check this before buying a sensor. | | Replace MAP sensor | $100-$350 | Usually held by one or two bolts and a connector. | | Repair vacuum or intake leak | $100-$600 | Hoses are cheap; intake gaskets cost more because of labor. | ## Is it safe to drive with P0106? > **Drive to a shop this week.** Usually safe to drive for short trips while you arrange a diagnosis. Wrong MAP readings can make the engine run rich or lean, which hurts fuel economy and can overheat the catalytic converter over time. Get it checked soon if the engine stalls, smells of fuel or blows black smoke. ## Will P0106 fail an emissions test? P0106 sets the check engine light, which fails an OBD-II emissions test in most states. A MAP sensor that misreads load can also push the fuel mixture off and raise emissions. Clearing the code resets the readiness monitors, so after the repair, drive several days of mixed city and highway trips before the inspection. ## After the repair: clearing P0106 After the repair, clear the code and check live data: key-on MAP should match barometric pressure, idle MAP should be low and steady, and the reading should jump smoothly when the throttle snaps open. Fuel trims should also settle near zero. Drive several trips; no pending code means the fix held. ## How to prevent P0106 - Inspect the MAP sensor hose for cracks or softness whenever the air filter is replaced. - Keep the PCV system in good shape so oil vapor does not coat the MAP sensor. - Reconnect vacuum lines carefully and check their routing after any intake or throttle body work. - Fix vacuum leaks and lean codes promptly so the MAP sensor reads true manifold pressure. ## Codes often seen with P0106 - [P0107](/codes/p0107): Manifold Absolute Pressure/Barometric Pressure Circuit Low - [P0108](/codes/p0108): Manifold Absolute Pressure/Barometric Pressure Circuit High - [P0101](/codes/p0101): Mass or Volume Air Flow "A" Circuit Range/Performance - [P0171](/codes/p0171): System Too Lean (Bank 1) - [P0172](/codes/p0172): System Too Rich (Bank 1) - [P0121](/codes/p0121): Throttle/Pedal Position Sensor/Switch "A" Circuit Range/Performance ## Frequently asked questions ### Can I drive with a P0106 code? Yes, in most cases you can drive with P0106 for a short time. The engine may idle rough, hesitate or use more fuel. Avoid long trips until it is fixed, and get it checked quickly if the car stalls, smells of raw fuel or blows black smoke from the exhaust. ### What is a MAP sensor? A MAP sensor measures air pressure inside the intake manifold, which tells the engine computer how hard the engine is working. The computer uses it to set fuel and ignition timing. On some engines it is the main load sensor, while on engines with a MAF sensor it serves as a backup and cross-check. ### What causes P0106? The most common cause of P0106 is a cracked, loose or clogged vacuum hose to the MAP sensor. A failing or contaminated MAP sensor and vacuum leaks are also common. Less often, low engine vacuum from a timing problem or clogged exhaust, or an intermittent wiring fault, sets the code. ### How much does it cost to fix P0106? Most P0106 repairs cost $50 to $600 at an independent shop. Replacing a MAP hose or O-ring runs $50 to $150, and a new MAP sensor $100 to $350. Repairing a vacuum or intake gasket leak costs $100 to $600, depending on which part leaks and how hard it is to reach. ### What is the difference between P0106, P0107 and P0108? P0106 means the MAP reading is out of range or implausible while the circuit still works. P0107 means the signal voltage is too low, and P0108 means it is too high, which usually points to wiring or a failed sensor. P0106 more often comes from hoses, leaks or a lazy sensor. ### Can a vacuum leak cause P0106? Yes, a large vacuum leak can cause P0106 because it raises manifold pressure at idle above what the computer expects with the throttle closed. Lean codes such as P0171 often appear alongside it. A smoke test is the quickest way to find leaks that are too small to hear. ### Can I fix P0106 myself? Often, yes. Checking and replacing the MAP hose, cleaning around the connector and swapping the sensor are usually simple jobs with basic tools. A scan tool that shows live MAP data helps confirm the fix. Smoke testing and engine vacuum checks are easier for a shop with the right equipment. ### Can a clogged catalytic converter cause P0106? Yes, it can. A badly restricted exhaust lowers intake vacuum, so the MAP sensor reads higher than expected even though it works correctly. Other signs include power loss at higher speeds and heat under the car. A vacuum gauge or exhaust back-pressure test confirms it before you replace the sensor. ### Does altitude affect P0106? Altitude changes barometric pressure, and the computer normally relearns it at key-on, so driving in the mountains should not set P0106 by itself. A sensor that drifts or responds slowly may show up more on big elevation changes, though. A shop can compare key-on MAP with local barometric pressure to check it. ### Should I clean or replace the MAP sensor? Replacing the MAP sensor is usually the better choice if testing shows it reads wrong, because most cannot be cleaned effectively. Gently clearing oil from the port and hose may help when contamination is the issue. Always check the hose and wiring first, since they are cheaper and more common causes. ## Sources - [SAE J2012: Diagnostic Trouble Code Definitions](https://www.sae.org/standards/content/j2012_201812/) - [EPA: On-Board Diagnostics (OBD)](https://www.epa.gov/state-and-local-transportation/vehicle-emissions-board-diagnostics-obd) ## Other air intake codes - [P0101 Mass or Volume Air Flow "A" Circuit Range/Performance](https://diagxcar.com/codes/p0101) - [P0102 Mass or Volume Air Flow "A" Circuit Low](https://diagxcar.com/codes/p0102) - [P0107 Manifold Absolute Pressure/Barometric Pressure Circuit Low](https://diagxcar.com/codes/p0107) - [P0108 Manifold Absolute Pressure/Barometric Pressure Circuit High](https://diagxcar.com/codes/p0108) - [P0112 Intake Air Temperature Sensor 1 Circuit Low (Bank 1)](https://diagxcar.com/codes/p0112) - [P0113 Intake Air Temperature Sensor 1 Circuit High (Bank 1)](https://diagxcar.com/codes/p0113) - [P0117 Engine Coolant Temperature Sensor 1 Circuit Low](https://diagxcar.com/codes/p0117) - [P0118 Engine Coolant Temperature Sensor 1 Circuit High](https://diagxcar.com/codes/p0118) - [P0121 Throttle/Pedal Position Sensor/Switch "A" Circuit Range/Performance](https://diagxcar.com/codes/p0121) - [P0122 Throttle/Pedal Position Sensor/Switch "A" Circuit Low](https://diagxcar.com/codes/p0122) ## Symptoms - [Why is my car idling rough?](https://diagxcar.com/symptoms/rough-idle) - [Why does my car hesitate when I accelerate?](https://diagxcar.com/symptoms/car-hesitates-when-accelerating) - [Why does my car stall while driving?](https://diagxcar.com/symptoms/car-stalls-while-driving) - [Why is black smoke coming from my exhaust?](https://diagxcar.com/symptoms/black-smoke-from-exhaust) --- Source page: https://diagxcar.com/codes/p0106 Updated: 2026-11-03 General information, not a substitute for a qualified mechanic.