P0300- Multi Miss Fire..... Help!
02-19-2010, 07:53 PM
#21
I have BBP but I don't have EFI Live. The light went off today on it's own after I put a qt. of Lucas injector cleaner in so I tried to go threw inspection and it still failed the Evap sys-not ready and O2 sensor heater-not ready.
I tried the brake clean on the intake while running and nothing happened. So that's a good thing, I hope that this problem is done and over with.
I tried the brake clean on the intake while running and nothing happened. So that's a good thing, I hope that this problem is done and over with.
I was going to go threw inspection tomorrow and now I can't. ***!
02-21-2010, 05:59 PM
#25
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Mine has been doing this for about 10,000 miles. It will come and go, I don't have headers and replaced the wires and plugs with no change. I cannot tell that it ever really misses so I have just been driving the wheels off it, I am glad that I don't have to go through emission testing. I think mine is related to an old O2 sensor issue that I have replaced. I know I have offered no help but just some support but, I am following along to see if you figure it out so that I can try the same thing.
02-21-2010, 07:16 PM
#27
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You can see cylinder specific misfire counts in Mode 6. P0300 means the ECM can't narrow down the specific cylinder pulses coming from the CKP or maybe they really are random. Look at Mode 6 to be sure. If you don't have an aftermarket camshaft(causes rough idle which is another way of saying the ECM "thinks" the engine is misfiring) you problem lies elsewhere. Why is your idle vacuum so low? Do you have excessive blowby? Are you running a catch can to check for blowby?
