P0106: MAP/Barometric Pressure Circuit Range/Performance (Meaning, Causes, Fixes)
What P0106 means
The MAP sensor measures the pressure (vacuum) inside the intake manifold, which tells the engine computer (PCM) how much load the engine is under. Per RepairPal, the PCM uses it to control the air-fuel ratio, ignition timing and several emission controls. OBD-Codes.com explains that the PCM expects any change in manifold pressure to follow a change in engine load, such as throttle angle, engine speed or EGR flow; if it sees a rapid change in the MAP reading without one of those, it sets P0106. RepairPal describes the trigger more generally as problematic or erratic performance in the MAP/Baro sensor signal. On some vehicles the barometric (BARO) sensor is built into the mass air flow (MAF) sensor and there is no separate MAP sensor, or the MAP sensor is only a backup for the MAF (OBD-Codes.com). P0106 is a generic code and doesn't by itself mean the sensor is bad. Related MAP circuit codes are P0105 (circuit), P0107 (circuit low), P0108 (circuit high) and P0109 (intermittent). The sources give slightly different voltage figures: OBD-Codes.com says roughly 1 to 1.5 volts at idle, about 4.5 volts at wide-open throttle and about 4.5 volts key-on engine-off, while RepairPal says readings typically range from about 4 volts or more when accelerating to 1 volt or less when decelerating. Check the specs for your vehicle.
Severity: can I keep driving?
Drive with caution, fix soon
Get it checked soon. RepairPal rates P0106 'Urgent', while OBD-Codes.com lists drivability symptoms such as rough running, black smoke and an engine that won't idle. If the engine stalls, won't idle or runs very rough, avoid driving it (especially in traffic) until it's fixed.
Common symptoms
- Check engine light on
- Engine runs rough or misses at speed (listed by OBD-Codes.com)
- Engine won't idle (listed by OBD-Codes.com)
- Black smoke from the tailpipe (listed by OBD-Codes.com)
- Hard starting (noted by RepairPal in some cases)
- Poor fuel economy
- In some cases, noticeably poor engine performance
Likely causes
Roughly most to least common, based on the sources below. Your vehicle may differ.
- Faulty MAP/barometric pressure sensor
- Intake manifold vacuum leak
- Damaged, restricted or disconnected MAP sensor vacuum hose, or a split sensor seal where the sensor plugs into the manifold
- Water or dirt in the MAP sensor connector, or corroded connections
- Open or short (often intermittent) in the MAP sensor 5-volt reference, ground or signal wire
- A break in the flexible air intake duct between the MAF sensor and the intake manifold (listed by OBD-Codes.com)
- Faulty PCM, rarely (OBD-Codes.com says rule out everything else first)
Diagnostic steps you can do
Work on a cool engine, parked on level ground with the parking brake set. Never work under a car supported only by a jack.
- Read all stored codes and note freeze-frame data. Lean codes such as P0171 or P0174 alongside P0106 can point to a vacuum leak.
- Inspect the MAP sensor vacuum hose for cracks, kinks, blockage or a loose fit. If the sensor plugs straight into the manifold, check its seal.
- Inspect the intake ducting and intake manifold area for vacuum leaks and split hoses.
- Check the MAP sensor connector for water, dirt, corrosion and loose pins, and look for damaged wiring.
- With a scan tool, compare the MAP and BARO readings with the key on and engine off. OBD-Codes.com says they should be roughly equal, and the MAP reading should drop noticeably once the engine starts.
- Clear the code and see if it returns before buying parts.
Typical fixes
- Repair intake or vacuum leaks
- Replace or reconnect a damaged MAP sensor vacuum hose or seal
- Clean or repair the MAP sensor connector and wiring
- Replace the MAP sensor once the hose, wiring and vacuum have been checked
- Repair a stuck-open EGR valve or faulty idle air control motor if that's the real cause (RepairPal lists both as reasons a MAP sensor gets replaced unnecessarily)
- Install a manufacturer software update where one applies to your vehicle
Repair costs vary widely by vehicle, region, parts brand and shop, so we don't quote prices. Get a written estimate after diagnosis.
🛠 When to call a pro
- The code returns after you've checked the hose, wiring and connector
- Testing needs a scan tool with live data, a hand vacuum pump and a voltmeter to check the 5-volt reference, ground and signal
- The engine stalls, won't idle or runs very rough
- RepairPal warns the MAP sensor is often replaced when the real cause is a vacuum leak, a stuck-open EGR valve or a bad idle air control motor, so avoid replacing parts on guesswork
Where to buy
Plain search links. Always match parts to your exact year, make, model and engine.
FAQs
Does P0106 mean I need a new MAP sensor?
Not necessarily. Both sources list vacuum leaks and wiring or connector problems as causes, and RepairPal says the MAP sensor is commonly replaced when the real problem is a vacuum leak, a stuck-open EGR valve or a bad idle air control motor.
Can a vacuum leak cause P0106?
Yes. RepairPal lists intake manifold vacuum leaks as a common cause, and OBD-Codes.com lists a break in the intake duct between the MAF sensor and the intake manifold.
Is it safe to drive with P0106?
RepairPal rates P0106 'Urgent', and it can cause rough running, a poor idle and bad fuel economy. Get it diagnosed soon, and don't drive if the engine is stalling or won't idle.
My car has no MAP sensor. Why do I have P0106?
OBD-Codes.com notes that some vehicles have the barometric pressure sensor built into the MAF sensor instead of a separate MAP sensor, so the code can relate to that sensor. Check a service manual for your vehicle.
Sources
Last reviewed 2026-10-22. Code definitions and repair steps can vary by manufacturer. Confirm with your vehicle's service information.