P0106 on Chevrolet: How to Diagnose & Fix
MAP/Barometric Pressure Circuit Range/Performance
4 Chevrolet models · 5 documented issues · 2 critical · $100-$7,500 repair
P0106 on Chevrolet by model: symptoms, diagnosis and fix
The 1.4L turbocharged Ecotec engine in the Sonic shares the notorious PCV system failure with the Chevrolet Cruze. The PCV regulator diaphragm integrated into the valve cover ruptures, causing massive vacuum leaks. Additionally, the intake manifold check valve (small red/orange valve) fails, compounding the issue. This affects virtually all 1.4T Sonics eventually, typically between 50,000-100,000 miles.
Common Symptoms
- Check engine light with P0171 (system too lean)
- Rough or unstable idle
- Excessive oil consumption between changes
- Hissing or whistling sound from engine area
- Poor acceleration and turbo boost loss
How to Fix
Replace the valve cover assembly (includes new PCV diaphragm) with the updated GM design. Replace the intake manifold check valve simultaneously. Inspect the corrugated PCV hose from intake manifold to turbo for cracks. Use only GM or quality aftermarket valve covers - cheap replacements fail quickly.
Sources for this issue (2)
The intake manifold on the 1.4T Cruze has variable-length intake runners controlled by an internal flap actuator. The actuator motor fails or the runner flaps stick due to carbon buildup and oil contamination (especially when the PCV valve cover has also failed). When the runners stick open or closed, the engine loses low-end torque, idles rough, and throws a check engine light. The plastic runner flap pivots can also break, sending debris into the intake port and potentially the cylinder.
Common Symptoms
- Check engine light with intake manifold codes
- Loss of low-end torque and sluggish acceleration
- Rough idle
- Engine hesitation during acceleration
- Rattling noise from intake manifold area
How to Fix
Clean the intake manifold runner flaps with throttle body cleaner and check the actuator motor for proper operation ($100-$200 for cleaning). If the actuator motor has failed, replacement costs $80-$200 for the part and 1-2 hours of labor. If the runner flaps are broken or cracked, the entire intake manifold assembly must be replaced ($200-$400 for parts, $200-$400 labor). Address any PCV valve cover failures first, as oil contamination from a failed PCV system accelerates carbon buildup on the runner flaps.
Sources for this issue (1)
The 1.4T engine in the first-generation Cruze has the PCV system integrated into the valve cover assembly. The PCV diaphragm ruptures, the check valve fails, or the valve cover gasket deteriorates, causing oil leaks, vacuum leaks, rough idle, and check engine lights. The failed PCV system creates excess crankcase pressure that pushes oil past seals and into the intake manifold. This is the same fundamental design flaw as the Equinox and Malibu 1.5T PCV system. GM released an updated valve cover with improved PCV components.
Common Symptoms
- Rough idle, especially when cold
- Check engine light with lean or misfire codes
- Oil leaking from valve cover area
- Whistling or hissing noise from engine (vacuum leak)
- Oil in intake manifold or intercooler piping
- Excessive oil consumption
How to Fix
Replace the entire valve cover assembly, which includes the integrated PCV system ($80-$200 for parts). Labor is 1-2 hours ($100-$250). Use the updated GM valve cover design (GM part 55573746 or later revision) with the improved PCV diaphragm. After replacement, check the intake manifold and intercooler for oil contamination — clean any oil found. Also replace the valve cover gasket even if using the same cover, as the gasket is a common secondary leak source.
Sources for this issue (1)
A defective supplier batch of valve springs went into GM V8 engines built between June 1 and September 15, 2020, including the 6.2L LT2 in the C8 Stingray. Springs broke at astonishingly low mileage — documented C8 failures at 57 miles and at 115 miles, one of which required a flatbed tow. A broken spring drops valve control on that cylinder, producing a misfire, an audible tapping or clattering engine noise, a check engine light, and in the worst case valve-to-piston contact that destroys the head or the engine. GM acknowledged the defect in service bulletin PIP5752A on September 22, 2020, covering seven V8 families (L87, LT1, LT2, LT4, L82, L84, L8T). Owners subsequently reported failures on engines built past the September 15 cutoff, and GM extended the affected build window, so the published date range should be treated as a floor rather than a boundary. This is a discrete supplier defect and is unrelated to the LT2's lifter-tick and DFM behavior.
Common Symptoms
- Check engine light with misfire codes
- Rough idle or unstable idle speed
- Ticking, tapping, or clattering from the engine
- Sudden loss of power at very low mileage
- Engine will not restart after failure
How to Fix
Have the dealer run GM PIP5752A. The bulletin requires a cylinder leakage test on the affected cylinder first. If no leakage is found on an LT-series engine built in the affected window, the correct repair is to replace all valve springs on both banks — not just the broken one — which is 16 springs for the 6.2L LT2. If leakage is present, further teardown determines whether the head, valve, or short block is damaged. GM required all removed springs be returned to Detroit for analysis, so confirm your dealer follows the return process rather than performing a partial repair. This work is covered by the 5-year/60,000-mile powertrain warranty. If your car's engine build date sits near or just past September 15, 2020 and you have misfire symptoms, push the dealer to open a case with GM rather than accepting a build-date denial, since the window was extended once already.
Sources for this issue (2)
Vans built with the 6.0L L96/LC8 Vortec V8 (the volume engine in Express 2500/3500 from 2010 on) can break a rocker arm, producing an engine tick and a hard misfire on one cylinder. GM addressed it in preliminary information bulletin PIP5522B, which specifically lists 2017-2018 Chevrolet Express among the affected vehicles and warns that a broken rocker arm can let the valve drop into the cylinder and cause catastrophic engine failure. Important generation/engine discipline: the Express 4.8L L20 and 6.0L L96 do NOT use Active Fuel Management, so the AFM collapsing-lifter story that plagues Silverado/Tahoe 5.3L and 6.2L engines does not apply to these vans - this is a rocker/valvetrain hardware failure, not an AFM lifter failure. Owners typically hear a distinct top-end tick that does not go away as the engine warms, followed by a stored misfire code. A separate, narrower valve-spring concern (GM PIP5752A) applies only to engines built roughly June 1 through September 15, 2020, and also touched Express production.
Common Symptoms
- Persistent top-end ticking that does not quiet as the engine warms
- Single-cylinder misfire
- Rough idle
- Check engine light with random or cylinder-specific misfire codes
- Loss of power
- Loud clatter followed by catastrophic noise if the valve drops
How to Fix
Diagnose the ticking cylinder with a cylinder-balance test and stored misfire data, then pull the valve cover on the affected bank and inspect the rocker arms and pushrods before assuming a lifter problem. If a rocker is broken, replace the rocker, its pushrod, and inspect the valve, seat and piston crown for contact damage - a dropped valve means a head or short-block replacement. Catch it early: continuing to drive on a broken rocker is what turns a few-hundred-dollar rocker job into an engine. There is no recall or free remedy; PIP5522B is a service bulletin, not a warranty extension, so coverage depends on remaining powertrain warranty. For 2020-build engines, PIP5752A directs replacing all valve springs on both banks if no cylinder leakage is found.
Sources for this issue (3)
- GM PIP5522B / PIP5752A discussion - 6.0L L96 engine noise and misfire from broken rocker arm; Express listed among affected vehiclestsb
- GM Issues Service Bulletin PIP5752A for Faulty V8 Engine Valve Springs (springs used across the lineup including the Chevy Express van)tsb
- P0300 on 2014-2018 Chevrolet Express: Random Misfire Causes and Fixesarticle
P0106 code reference
General diagnostic-code context. The code alone does not confirm a cause for your vehicle; use the applicable issue card and its sources.
Frequently asked questions
What does P0106 mean on a Chevrolet?
P0106 stands for "MAP/Barometric Pressure Circuit Range/Performance." P0106 means the manifold absolute pressure (MAP) or barometric pressure sensor signal is out of the expected range or not matching engine operating conditions (range/performance). The MAP sensor measures intake manifold pressure/vacuum, which the computer uses to gauge engine load and calculate the correct fuel and ignition timing. When the reading is implausible — too steady, not tracking throttle changes, or inconsistent with other sensors — the computer flags this code. Symptoms often include rough idle, hesitation, poor fuel economy, or a lack of power, and the cause may be the sensor, a vacuum leak, or wiring. On Chevrolet it is documented across 4 models: Sonic, Cruze, Corvette, Express.
What are the most common causes of P0106?
The most common causes of P0106 are: Faulty MAP sensor, Vacuum leak or disconnected/cracked vacuum line to the sensor, Clogged or restricted MAP sensor port, Wiring or connector problems in the sensor circuit, Intake manifold leak affecting pressure readings, Restricted air intake or exhaust affecting manifold pressure, Poor ground or reference voltage to the sensor. The specific cause varies by vehicle.
How much does it cost to fix P0106 on a Chevrolet?
Published repair estimates on Chevrolet range from $100 to $7,500 depending on the model and root cause. If an issue mentions a recall or campaign, check your VIN with the manufacturer or NHTSA and confirm eligibility and coverage with a dealer.
Looking for P0106 on a different make?
View P0106 across all makes →Content compiled with AI assistance using NHTSA complaints, TSBs, and owner reports. May contain errors. Always verify with your vehicle's service manual.