Loss of power: Codes, Causes & Fixes

P0174 Powertrain The cylinder bank without cylinder 1 is running lean even with the maximum fuel correction… Moderate P0300 Powertrain The engine computer sees misfires that jump between cylinders or hit several cylinders at once. High P0420 Powertrain The bank 1 catalytic converter no longer stores enough oxygen to clean the exhaust properly. Low P0430 Powertrain The bank 2 converter on a V6, V8 or split-exhaust engine isn't cleaning the exhaust well enough. 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

P0342 Powertrain The bank 1 cam sensor signal stays near 0 volts. Often a weak battery, a pinched wire… Moderate P0343 Powertrain The bank 1 cam signal is stuck high: an unlatched connector, broken ground or open wire after… Moderate P0345 Powertrain The cam sensor on bank 2, the side without cylinder 1, has a missing or faulty signal on a V6… Moderate P0346 Powertrain Bank 2's cam signal arrives out of position. On V6/V8s that often means a bank 2 chain, guide… Moderate P0351 Powertrain The engine computer found an electrical fault in coil A, the coil that fires cylinder 1 on most… Moderate P0352 Powertrain Coil B, normally on cylinder 2, has a circuit fault. Where cylinder 2 sits depends… Moderate P0353 Powertrain The circuit for coil C, which fires cylinder 3, failed its electrical check. Wiring is a big… Moderate P0355 Powertrain Coil E, the coil for cylinder 5, has an electrical fault. Only engines with five or more… Moderate P0356 Powertrain The coil F circuit for cylinder 6 failed its check. On inline sixes it's the coil… Moderate P0357 Powertrain Coil G, which fires cylinder 7 on V8s, has an electrical fault. On GM trucks it sits by… Moderate P0366 Powertrain Bank 1 exhaust cam signal is out of position: chain stretch, a sticky exhaust phaser… Moderate P0402 Powertrain More exhaust is being recirculated than the ECU asked for, usually because the EGR valve won't… Moderate P0471 Powertrain The exhaust backpressure reading doesn't match what the computer expects; the sensor tube… Moderate P0472 Powertrain Exhaust backpressure sensor signal near zero volts: dead sensor, grounded wire or lost 5 V… Moderate P0524 Powertrain Measured oil pressure fell below the safe minimum. Stop the engine now and check the oil before… Critical P0573 Powertrain The PCM thinks the brake pedal is always pressed – brake lights stay on, often from a missing… Moderate P0607 Powertrain A general internal performance check in the engine computer failed – supply, grounds… Moderate P061B Powertrain The ECM's safety monitor disagreed with its own engine torque calculation – often bad input… Moderate P0642 Powertrain The PCM's 5-volt supply 'A' is being pulled below spec, usually by a short to ground in one… High P0651 Powertrain The PCM's second 5-volt sensor supply is out of range – usually a pedal, throttle or pressure… Moderate P069E Chevrolet · Powertrain The fuel pump control module stored its own fault and asked the engine computer for the check… Moderate P0730 Powertrain The transmission computer sees input and output shaft speeds that don't fit the gear it… High P0731 Powertrain While in first gear, the transmission's input and output speeds don't match the first-gear… Moderate P0733 Powertrain Third gear slips: input shaft speed doesn't match output speed times the 3rd-gear ratio. Moderate P0751 Powertrain Solenoid A is wired fine but its valve isn't doing its job, so gears are missing – often stuck… High P0756 Powertrain Solenoid B isn't moving fluid the way the TCM expects – the car may pull away in 3rd or 4th. High P0868 Powertrain Measured transmission line pressure is below what the TCM commanded – clutches can slip… High P0894 Powertrain The transmission computer measured slip inside the gearbox that shouldn't be there. Clutches… High P0A0F Powertrain The hybrid system spun the gas engine with its motor-generator to start it, but the engine… High P0A1F Powertrain The module that manages the high-voltage battery failed its self-check or reports implausible… Moderate