Cause
Restricted air filter
A filter blocked enough to restrict flow. The engine still gets what it asks for at idle and cannot at full throttle, so the complaint is a loss of top-end power with a normal tickover — and on engines that measure airflow directly, the module fuels correctly for the reduced air and the driver simply gets less engine.
Typically an easy fix. Often worth checking before paying anyone to look.
Codes this can cause (20)
Codes where this is a likely explanation first, rather than merely a possible one.
- P0101 Mass or Volume Air Flow Sensor A Circuit Range/Performance Likely for this code High
- P012B Turbocharger/Supercharger Inlet Pressure Sensor A Circuit Range/Performance Likely for this code Moderate
- P0172 System Too Rich — Bank 1 Likely for this code High
- P0175 System Too Rich — Bank 2 Likely for this code High
- P032F Combustion Engine Producing Insufficient Torque Likely for this code High
- P2074 Manifold Absolute Pressure/Mass Air Flow — Throttle Position Correlation at Higher Load Likely for this code Moderate
- P2192 System Too Rich at Higher Load Bank 1 Likely for this code Moderate
- P2280 Air Flow Restriction/Air Leak Between Air Filter and Mass Air Flow Sensor Bank 1 Likely for this code Moderate
- P2375 Turbocharger/Supercharger Inlet Pressure Sensor B Circuit Range/Performance Likely for this code Moderate
- P0102 Mass or Volume Air Flow Sensor A Circuit Low High
- P0127 Intake Air Temperature Too High Moderate
- P012A Turbocharger/Supercharger Inlet Pressure Sensor A Circuit Moderate
- P026D Fuel Injection Quantity A Higher Than Expected Moderate
- P0299 Turbocharger/Supercharger A Underboost Condition High
- P0506 Idle Air Control System RPM Lower Than Expected Moderate
- P2178 System Too Rich Off Idle Bank 1 Moderate
- P2188 System Too Rich at Idle Bank 1 Moderate
- P2194 System Too Rich at Higher Load Bank 2 Moderate
- P2262 Turbocharger/Supercharger Boost Pressure A Not Detected — Mechanical High
- P2459 Particulate Filter Regeneration Frequency — Bank 1 Moderate
Information, not instruction
CarGeek is a reference, not a service manual. Its pages are written from public sources and from what other people have found, never from a manufacturer's own service information, so they can be wrong or incomplete for your particular vehicle. Some of what they describe carries real risk: high voltage, fuel under pressure, stored energy, hot and moving parts.
Have anything you intend to act on checked by a trained person against the manufacturer's own procedure for your vehicle. Nothing here replaces that procedure.
Others who found this
Be the first to write this up
Nothing posted about this yet. Whatever you found is worth writing down — even a dead end saves someone the same afternoon.
What makes one worth reading:
- The car — make, model, year and engine. The same fault behaves differently on each.
- What you measured, not only what you replaced.
- What actually fixed it — or that nothing did, which is worth knowing too.
Sign in or create an account to add what you found about Restricted air filter.