Codes
OBD2 Trouble Code Library
Your check engine light means something specific. Look up the code for a plain-English answer: what it means, how serious it is, when to get it checked, and the likely causes.
Fuel & Air
- P0087Fuel pressure is too low to feed the engine properly
- P0088Fuel pressure is too high and could flood the engine
- P0089The fuel pressure regulator is not holding steady pressure
- P0093The fuel system has a significant leak
- P0171your engine is getting too much air and not enough fuel
- P0172Your engine is burning too much fuel on the driver side
- P0174Your engine is not getting enough fuel on the passenger side
- P0175Your engine is burning too much fuel on the passenger side
- P0201The fuel injector circuit for cylinder 1 has a fault
- P0202The fuel injector circuit for cylinder 2 has a fault
- P0203The fuel injector circuit for cylinder 3 has a fault
- P0204The fuel injector circuit for cylinder 4 has a fault
- P0505The idle speed control system is not working properly
- P0506The engine is idling too low
- P0507The engine is idling too high
Ignition & Misfire
- P0300Your engine is misfiring, and the computer cannot pin it to one cylinder
- P0301Cylinder 1 is misfiring and not burning fuel right
- P0302Cylinder 2 is misfiring
- P0303Cylinder 3 is misfiring
- P0304Cylinder 4 is misfiring
- P0305Cylinder 5 is misfiring
- P0306Cylinder 6 is misfiring
- P0307Cylinder 7 is misfiring
- P0308Cylinder 8 is misfiring
- P0316Your engine misfired right after it started
- P0341The camshaft position sensor is sending an unexpected signal
- P0344The camshaft position sensor signal is cutting in and out
- P0345The camshaft sensor on the second cylinder bank has a problem
Emissions & EVAP
- P0130The upstream oxygen sensor on the left side has a circuit problem
- P0131The upstream oxygen sensor on the left side is reading lean all the time
- P0132The upstream oxygen sensor on the left side is reading rich all the time
- P0133The upstream oxygen sensor on the left side is responding too slowly
- P0134The upstream oxygen sensor on the left side has stopped working
- P0401The EGR system is not flowing enough exhaust gas
- P0411The secondary air injection pump is not moving enough air
- P0440There is a general fault in the fuel vapor containment system
- P0441The EVAP purge valve is not flowing the right amount of vapor
- P0442There is a small leak in your fuel vapor system
- P0443The EVAP purge valve has a circuit fault
- P0446The EVAP vent valve has a circuit fault
- P0449The EVAP vent solenoid circuit is not working
- P0451The EVAP fuel tank pressure sensor is reading out of range
- P0455Your car found a large leak in the fuel vapor system
- P0456There is a very small leak in the fuel vapor system
- P0457The gas cap is loose or missing and vapors are escaping
Sensors
- P0101The mass air flow sensor is reading outside its expected range
- P0102The mass air flow sensor is sending a signal that is too low
- P0106The MAP sensor is reading outside its expected range
- P0107The MAP sensor voltage is too low
- P0108The MAP sensor voltage is too high
- P0113The intake air temperature sensor is reading too high
- P0121The throttle position sensor is reading outside its expected range
- P0122The throttle position sensor voltage is too low
- P0123The throttle position sensor voltage is too high
- P0135The upstream oxygen sensor heater on the driver side is not working
- P0136The downstream oxygen sensor on the driver side has a circuit fault
- P0137The downstream oxygen sensor on the driver side is reading too low
- P0138The downstream oxygen sensor on the driver side is reading too high
- P0141The downstream oxygen sensor heater on the driver side is not working
- P0155The upstream oxygen sensor heater on the passenger side is not working
- P0161The downstream oxygen sensor heater on the passenger side is not working
- P0325The knock sensor circuit on Bank 1 has a fault
- P0332The knock sensor circuit on Bank 2 is reading too low
- P0335Your engine's crankshaft position sensor signal is missing or unreliable
- P0336The crankshaft position sensor signal is intermittent or out of range
- P0340The camshaft position sensor on Bank 1 has a circuit fault
- P0500The vehicle speed sensor is not sending a reliable signal
- P2135The two throttle position sensors do not agree with each other
- P2138The two accelerator pedal position sensors do not agree
Catalytic Converter
- P0420Your catalytic converter is not cleaning exhaust like it should
- P0421The warm-up catalytic converter is not cleaning exhaust well
- P0430Your bank 2 catalytic converter is not cleaning exhaust like it should
Transmission
- P0700Your transmission computer found a fault and turned on the light
- P0705The transmission cannot read which gear you have selected
- P0715The transmission cannot measure its input shaft speed
- P0740The torque converter lockup clutch has a circuit fault
- P0755Transmission shift solenoid B has a fault
Other
- P0010The engine cannot control intake cam timing on the left side
- P0011Your engine's variable valve timing is stuck too far advanced
- P0012The intake cam on the left side is stuck too far retarded
- P0013The engine cannot control exhaust cam timing on the left side
- P0014The exhaust cam on the left side is stuck too far advanced
- P0016The crankshaft and intake cam positions do not match on the left side
- P0017The crankshaft and exhaust cam positions do not match on the left side
- P0020The engine cannot control intake cam timing on the right side
- P0021The intake cam on the right side is too far advanced
- P0022The intake cam on the right side is stuck too far retarded
- P0125The engine is taking too long to reach normal operating temperature
- P0126Coolant temperature is too low for stable engine operation
- P0128Your engine is running too cold to warm up right
- P0217The engine overheated
- P0234Your turbocharger is producing more boost pressure than it should
- P0243The wastegate control solenoid for your turbocharger has failed
- P0245The wastegate solenoid circuit is reading abnormally low voltage
- P0299Your turbo is making less boost than the computer asked for
- P0562The electrical system voltage is running too low
- P0563The electrical system voltage is running too high
- P0600The engine computer has a communication network fault
- P0601The engine computer has a memory error
- P0606The engine computer processor has a fault
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