RAMnGO

Well for about the last 3 days my car has started to backfire and miss. If you idle it'll backfire thru the exhaust, and under a load it'll miss and stumble.. i changed teh drivers side spark plugs tonite didn't help i'm going to change teh passengers plugs tomorrow....but a friend seemed to think it was possible that it could be a burnt valve. If it was a burnt valve wouldn't the power go way down though? the car does ok if you're just cruising around on the highway but around town it sux...

wrencher

iTrader: (2)

If it was a valve, would be there all the time...


Check plugs & wires.

Run it at idle at night wet down wires w/water & see if you get a light show.

RAMnGO

well heres some mroe info, ALL the plugs seemed to say the engine is running lean but not by much ..i have pics of the plugs, the wires checked out ok.. tomorrow i will again reset teh PCM and try it then. but the thing i wonder about is how can i be using so much damn gas and it be almost lean? i mean i can drive for about 20 minutes and use a quarter of a tank and this is highway driving too... also does the PCM really know everything thats going wrong with the engine?
why wouldn't the SES light have come on if i had a bad plug if its that smart?? reason i'm asking these questions is i don't think this is a matter of plugs and wires, i'm getting a bit worried that since i haven't ever had my PCM changed since cam/head swap back in June i might have done some damage...

The Alchemist

iTrader: (19)

So to clarify, you have stage 2 heads, tr 224 cam, lt headers, and an x pipe and you haven't had it tuned? You really should look at getting it onto a dyno and have a wideband tune done to make certain your making the power you should be.

RAMnGO

well can't afford it right now but i'm getting ready to go finish the car up and see if it was the passengers side plugs maybe....

sawedoff

iTrader: (3)

A burnt valve, it is not. When was the last time you changed your fuel filter? On the street, it should be changed every 10,000mi. You might seriously consider having your injecors flow balanced and blue printed. I would also, invest in some super high quality ignition wires with the setup you have, and not use the cheap **** that the majority of speedshops sell. I use a brand of wire called Magnecor. www.magnecor.com For a fuel filter, I don't use an OEM fuel filter, but a Canton Racing "GM EFI filter #CM-15." It is compatible with the OEM style fuel lines and connectors. With what your describing, it sounds like it's definitely ignition related. I will also bet it's fuel system related, in one of the areas I talked about.