99SS-T

iTrader: (5)

I have been out racin about the last couple days and tonight i noticed that i had a bad misfire between 5300-6k. It came all of a sudden never did this before but does it EVERY time now. I changed the plugs and that didnt change anything. I checked to see if all my wires were connected to the coils and the plugs. I checkd in the dark to see if there was any arking. Didnt find anything. I have a 99 Camaro SS with mac headers/y-pipe flowmaster exhaust DIY TB and MAF ends. Other wise the car is stock as far as power goes. The plugs were all white when i pulled them, a couple had some corrosion to the porcelen(spelling) and some very small flecks of buildup. Those plugs consiquently are the stock plugs with 67k on them, while the mosly regular looking ones have about 20k on them. Like i said i have NEVER had a problem with the engine or electrical. This started just tonight. Hope someone has a idea as i think that chevy will give me the if i try to get it warrenteed. Thanks all


John

99SS-T

iTrader: (5)

ne1 have an idea?



John

jimmyblue

iTrader: (11)

Really hard, hot, lean running could chew back the
electrodes and give you more plug gap than you
originally had, needing more firing voltage than maybe
you can get off the coils. Did you regap the plugs or
check gap when you had them out?

Mix-n-match plugs is questionable in my mind.

Then again it's possible that the night of hard running
pushed your fuel trimming around some, to an unusual
place (like the MAF ends would be expected to fake
you lean, adding + trimming, which then re-enriches the
top end; if for some reason your trims go back down,
the WOT fueling would drift leaner and maybe produce a
short-fuel top end).

I know after my last trip to the track, my car was having
a hard time finding idle for a couple of days afterward.
Fuel trim learning is not necessarily a good thing (it just
gets you past type certification with the EPA and annual
smoggery, should you be so lucky).

99SS-T

iTrader: (5)

When i pulled out the old plugs they were all pretty much the same as spec. 60 is the gap i set the new ones to just like it says on teh hood to gap them. I see ya wrote that mixing and matching plugs isnt a good thing to do. Well hat wasent my plan back when i put them in . I put all new plugs in but i did it BEFORE i put the new headers in. So i ended up crackin 4 plugs and had to replace them. Now mind you this is at 2 in the mornin and i wanna get it going and hear it. So i just put the stock plugs back in where the broken ones were. Currently there is all brand new plugs in there. Now if it is a bit of pcm takin over and messing around how can i combat that? ya think i shoudl jsut unplug the battery for a bit to try to reset it all in hopes that that does it? The misfire happened EVERY time that i got to 5300 so its not liek this seems to be getting better or worse. Thanks for the reply man.



John