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I have a problem with my C6
I have a lot of misfires always on cylinder 7 (I have a Tech 2) and sometimes the P0300 code appear
When driving : lot of "bang" when decelerating and some hesitations when accelerating
I have swapped the coils, changed the spark plugs, replaced the plug wires. And still have the problem on the same cylinder
Any thougts about it ?
Assuming that the ignition system wiring is OK the only 2 things left are fuel and mechanical...what do your fuel trims look like when it’s misfiring ??...an injector related misfire will cause the fuel trims to be quite elevated !!...on the mechanical side possibly a broken valve spring (I’m leaning towards this)...you can check your fuel trims with the Tech 2 hooked up while your driving and if it misfires see what your fuel trims look like...your long term on bank 1 may be 13-15% positive. Also do you mean “back fire” as bang ??
Thanks for your answerI cammed my vette last year and put on dual Springs but I will have a look on them
I will also swap the cylinder 7 injector if it could be fuel related
Yes I mean backfire
You will just have to assume the injector wiring is good when you swap the injectors !!...I like to current ramp suspect injectors just to make sure I’m not losing power or ground or that the injector itself is not shorted...each injector draws about 1 AMP of current...this is what I like to see with a scope.
Well...
Valve springs are all ok and injector is not bad
Could a weak battery cause those problems (car stayed parked 6 months as I was waiting my clutch kit)? I noticed a lot of misfires on cylinder 7 but some also appears on the others cylinders
Yes, a bad battery can cause all kinds of driveability issues including misfires...coil packs and injectors draw quite a bit of current and the PCM doesn’t like it either...I would have the battery load tested and then make sure the battery cables on both ends are clean and secure !!
Stupid question but does this gen Corvette utilize AFM? Does it have a 4cyl. mode? If so, I would suspect a lifter going south. It is common on trucks with AFM.
Well New battery and still misfiringMainly cylinder 7 but few on others cylinders alsoSame problem so To sum UP it IS not the battery, coils, plugs, plugs wires, valve spring and injectors I forgot to mention it is during accélérationswhat should I look then ? O2 sensors maybe ?
P0300 code
