Check Engine Codes P0300 and P0140/P0160
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Check Engine Codes P0300 and P0140/P0160
Can anyone please tell me what is the cause of these codes? I have a 2002 Z06 with the following codes: P0300 (Engine Misfire) and P0140/P0160 (Circuit Insufficient Activity). A guy at AutoZone that scanned it said that it's most likely an O2 sensor, but would like to know for sure without having to spend $250 for a diagnostic fee at the dealership. I need to know ASAP, as I'm trading in this car on Friday and it needs to be fixed by Thursday night.
Thanks,
BrandoManZ06
Thanks,
BrandoManZ06
Moderator, Tech Contributor
Joined: Sep 2013
Posts: 15,406
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From: Cape Coral, Florida
The 2 Powerplant DTC’s can either be a bad O2 sensor or a wiring issue…a misfire can be many things as shown below…a dealership would be the LAST place I would take it to for a diagnosis as they will only replace parts until they fix it…find a diagnostic shop in your area that has the advanced equipment needed to diagnose it.
Plug
Wire
Coil Pack
Coil Pack wiring
Fuel Injector
Fuel Injector wiring
Fuel Injector wiring- bad ECM/PCM
Valve Spring broken
Burned Valve
Cam Lobe worn
Low Compression- Rings
O2 sensor- bank specific
Plug
Wire
Coil Pack
Coil Pack wiring
Fuel Injector
Fuel Injector wiring
Fuel Injector wiring- bad ECM/PCM
Valve Spring broken
Burned Valve
Cam Lobe worn
Low Compression- Rings
O2 sensor- bank specific
