After leaving class last night I jump in my truck and start it and it has a miss. It' a 04 Tahoe with a 5.3 it has never given me any problems. About 30k ago I did a tune up on it and installed E3 plugs I'm beginning to wonder if one has crapped out on me. As the truck warms up the more you can notice the miss. Anyone have this problem and do you think it could be the plugs?? I will be scanning it today on my lunch break to hopefully find the problem.

 

if it's throwing a code (check engine light is on) then the plug is probably cracked or you've got a bad wire. take off each plug wire and see if it makes a difference in how the engine runs. if it runs worse, then try the next one, if it makes no difference, you've found which cylinder isn't firing. if the plug isn't cracked or misfiring, you can check the wire by swapping with another cylinder. if that's not it, then you may have a bad coil.

Miles, Mods?

 

I kinda checked them all really quick last night when I got home. I unplugged all the wires at the coil and they all sparked when the wire was close so I don't think its a coil and it really didn't make a difference. After I scan it on my lunch I'll post the codes. The CEL just pretty much blinks constantly.

 

120k e3 plugs, corsa cat back, and Volant intake.

 

i believe they are Taylor wires

 

open hood at night, grab a bottle of water, and don't spray, but <mist> over the engine. Look for blue arcs, see if you have a crack in the plug porcelain or wire. Make it dark as possible, easy to pot possible wire/plug damage.

 

Could be a broken valve spring as well.

 

Flashing CEL=misfire of over 50%, or enough to cause catalytic converter damage. I've heard nothing but negatives about the e3 plugs, or most Bosch electronics for that matter, so I wouldn't doubt that one of them has taken a dump. You can get some NGK TR5 copper plugs for under $2 a piece, or go for the TR5ix which is iridium and will last much longer. If swapping plugs doesn't fix it, could be a bad injector or something mechanical that would require a compression test.

 

well just finished gutting that cats and it still has a miss.
i scanned it and it came up randow miss fire p0300
i plan on changing the plugs tonight was i get home

 

well after I limped my hoe home I threw a new set of NGK TR5's in it and back to purring like a kitten. I would highly recommend anyone considering using E3 plugs to steer clear. I hap approx 15K before they crapped out. Thanks to everyone that helped me out.

At least the tune I have been putting of will come sooner than later since I need my rear O2's tuned out.