Ignition & Misfire Trouble Codes: List & Fixes

P03xx codes cover misfires and the sensors the engine needs to time ignition. P0300 means random or multiple misfires; P0301 to P0312 name the cylinder that is misfiring; crankshaft and camshaft position sensor codes also sit in this range. On coil-on-plug engines, swapping the coil from the misfiring cylinder with a neighboring one and seeing whether the misfire follows is a quick, cheap first test. If the check engine light is flashing, reduce load and get the car checked promptly to protect the catalytic converter.

66Codes

3.0Average severity

15%High or critical

12%DIY-friendly

Severity distribution

Most viewed

P0300 Powertrain The engine computer sees misfires that jump between cylinders or hit several cylinders at once. High P0302 Powertrain Cylinder 2 keeps misfiring. On inline engines it's a middle cylinder, so rule out coolant… Moderate P0303 Powertrain Cylinder 3 is misfiring. Check whether it misses at idle or under load before you blame… Moderate P0304 Powertrain Cylinder 4 is misfiring. Its end or rear position makes water, oil and intake leaks common… Moderate P0325 Powertrain The computer isn't getting a usable signal from knock sensor 1, so it pulls timing to protect… Low P0335 Powertrain The engine computer lost the crankshaft position signal. Expect stalling or a crank-no-start. High

All codes (66)

All Severity 3+ Severity 4+

P0350 Powertrain The shared coil feed, ignition module or coil wiring is faulty. Often set with several… 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 P0354 Powertrain Coil D, normally the one on cylinder 4, failed its circuit check. It often shows up right after… 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 P0358 Powertrain Coil H, for cylinder 8, has an electrical fault. On nearly every V8 it's the hardest coil… Moderate P0365 Powertrain The exhaust cam sensor on bank 1 has lost its signal. Usually a heat-damaged sensor… Low P0366 Powertrain Bank 1 exhaust cam signal is out of position: chain stretch, a sticky exhaust phaser… Moderate P0369 Powertrain The bank 1 exhaust cam signal drops out now and then. Usually heat or vibration at the sensor… Low P0380 Powertrain The diesel glow plug circuit A (relay, fuse, wiring or the plugs as a group) isn't drawing… Low P0381 Powertrain The circuit for the dash wait-to-start light has a fault. The glow plugs themselves may still… Minor P0670 Powertrain The engine computer can't properly control or hear back from the diesel's glow plug control… Low P0671 Powertrain The glow plug in cylinder 1 or its wire isn't drawing normal current. Usually the plug itself… Low P1300 Toyota · Powertrain Toyota's ECM fires ignition coil No. 1 but gets no confirmation pulse (IGF) back from its… Moderate P1305 Toyota · Powertrain The igniter in Toyota coil No. 2 stops confirming its sparks, often only once the engine is hot. Moderate P1310 Toyota · Powertrain No spark confirmation from one Toyota coil: No. 3 on four-cylinders, but a different coil… Moderate P1320 Nissan · Powertrain The Nissan ECM isn't seeing the ignition primary signal it expects while the engine cranks… Moderate P1326 Hyundai · Powertrain Hyundai's KSDS software heard vibration typical of worn rod bearings and put the engine in limp… Critical P1326 Kia · Powertrain Kia's engine computer detected early rod-bearing wear through the knock sensor and capped… Critical P1336 Ford · Powertrain The Ford PCM sees the cam and crank signals out of step, usually from a mistimed or worn cam… Moderate P1340 Volkswagen · Powertrain The cam signal no longer lines up with the crank signal – often a jumped belt or stretched… High P1345 Chevrolet · Powertrain The cam signal is out of step with the crank signal; on Vortec engines usually a mis-set… Moderate P1346 Toyota · Powertrain Toyota's ECM sees the intake cam signal in the wrong place relative to the crankshaft signal. Moderate P1349 Toyota · Powertrain Toyota's VVT-i system isn't moving the intake camshaft to the position the ECM is asking for. Moderate P1361 Honda · Powertrain The top dead center (TDC) sensor signal keeps dropping out for a moment while the engine… Moderate P1362 Honda · Powertrain The PCM gets no signal at all from the top dead center (TDC) sensor; stalling or a no-start… High P1380 Chevrolet · Powertrain A misfire was detected, and the ABS module couldn't supply rough-road data to confirm it wasn't… Moderate

Subsystems

Fuel & Air Metering 193 Emission Controls 97 Speed & Idle Control 57 Transmission 57 ECU & Outputs 54 Module Communication 43 Brakes, ABS & Chassis 36 Body Systems 31 Hybrid / EV 14