Loss of power: Codes, Causes & Fixes

P0420 Powertrain The bank 1 catalytic converter no longer stores enough oxygen to clean the exhaust properly. Low P0101 Powertrain The MAF sensor's airflow reading doesn't match what the engine computer expects… Low P0171 Powertrain The engine computer is adding the maximum extra fuel it's allowed on bank 1 and still sees… Moderate P0174 Powertrain The cylinder bank without cylinder 1 is running lean even with the maximum fuel correction… Moderate P0299 Powertrain The turbo or supercharger isn't building the boost pressure the engine computer is asking for. Moderate P0300 Powertrain The engine computer sees misfires that jump between cylinders or hit several cylinders at once. High

P0001 Powertrain The PCM can't drive the solenoid that meters fuel into the high-pressure pump. Often a no-start… High P0008 Powertrain Camshaft timing on bank 1 has drifted from the crankshaft. Often a stretched timing chain. Moderate P0012 Powertrain The bank 1 intake cam lags behind the angle the PCM wants, often from chain stretch or weak oil… Moderate P0014 Powertrain The bank 1 exhaust cam won't follow its target and stays too far advanced; think oil, valve… Moderate P0015 Powertrain The bank 1 exhaust cam sits later than commanded; a stretched chain or stuck exhaust phaser… Moderate P0016 Powertrain The bank 1 intake cam and the crankshaft are out of step, most often from a stretched or jumped… High P0018 Powertrain The bank 2 intake cam is out of step with the crankshaft on a V or boxer engine; chain wear… High P0019 Powertrain The bank 2 exhaust cam signal doesn't match the crankshaft; chain, bank 2 exhaust phaser… Moderate P0022 Powertrain The bank 2 intake cam can't advance as far as the PCM asks; phaser, oil pressure or a worn bank… Moderate P0026 Powertrain The oil-operated valve control on the bank 1 intake side isn't responding as commanded. Check… Low P0028 Powertrain A bank 2 valve lift solenoid didn't produce the expected result; low or old oil is the most… Low P0045 Powertrain The engine computer sees an open or shorted circuit to the solenoid that controls turbo boost. Moderate P0046 Powertrain The boost control solenoid circuit is intact, but boost doesn't follow what the solenoid… Moderate P0069 Powertrain With the engine stopped, the manifold pressure and barometric pressure readings don't agree. Low P0081 Powertrain Electrical fault in the bank 2 intake cam solenoid on a V6 or V8; only one cylinder bank loses… Low P0087 Powertrain Measured fuel pressure has dropped well below what the engine computer is asking for. High P0089 Powertrain The fuel pressure regulator is getting its commands but pressure isn't responding the way it… Moderate P0090 Powertrain The engine computer sees an electrical fault in the wiring or coil of the fuel pressure control… Moderate P0093 Powertrain Rail pressure is dropping faster than injection explains: fuel may be escaping. Stop and check… Critical P0101 Powertrain The MAF sensor's airflow reading doesn't match what the engine computer expects… Low P0102 Powertrain The MAF signal is too weak for the PCM to accept, so it treats the circuit as dead… Moderate P0106 Powertrain The MAP sensor works electrically, but its pressure reading doesn't fit what the engine… Low P0107 Powertrain The MAP signal has fallen to almost zero volts, usually from a lost 5-volt reference or an open… Moderate P0112 Powertrain The IAT signal is near zero volts, so the PCM believes the intake air is scorching hot, usually… Low P0121 Powertrain The throttle position reading is electrically valid but doesn't agree with engine load, airflow… Moderate P0122 Powertrain The throttle position signal fell to nearly 0 volts, lower than a closed throttle could ever… Moderate P0131 Powertrain The upstream oxygen sensor on bank 1 keeps reporting a voltage so low that it reads as a lean… Low P0151 Powertrain Bank 2's front O2 sensor is stuck at a lean reading – often a manifold leak on that side… Low P0152 Powertrain Bank 2's front O2 sensor is pinned high – usually voltage leaking in from its heater wire… Moderate P0171 Powertrain The engine computer is adding the maximum extra fuel it's allowed on bank 1 and still sees… Moderate