PO300 Multiple Misfires?
#1
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I have a SES light on, now it comes and goes. I went to the track a couple weeks ago and back shifted from 4th into 2nd. Common right? Well, my friend and I figured I bent some push rods, So Don (SloHawk) took care of that problem for me by installing straight ones, I also put new AC Delco Plugs in and new MSD 8.5 wires and still the cars SES light comes on. What else could be happening? Please help this is getting aggrivating. Oh yeah I also have taken out the PCM Battery fuse to reset everything to relearn the car or however its supposed to work. Thanks
#2
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May have bent some valves when you missed the shift. Pressurize the cylinders with an air hose like you are changing valve springs and listen for air leaking. One more reason to change the valve springs to better ones even when running a stock cam.
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yeah I probably should have the cylinders pressure tested. I have heard this before, and maybe its time to get it done. I just want to fix it so i can get back to the track before it closes.
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a P0300 may also mean only 1 cylinder is misfiring. I had that code recently; turns out one of the spark plugs was cracked.
replaced it, no more SES light.
replaced it, no more SES light.