94Z has a missfire thats driving me nuts. Sometimes it doesnt effect my performance, and at other times the car BARELY goes.

Here is what I have done so far. (Yes I'm broke as hell)

OEM Optsipark and oem plugwires. Ran much better but still had the miss.

Put in Delteq.com coil pack conversion and new wires again and 8 new expensive plugs..
Wires starts arching all over the place. At night it was like a dang prade going on under my hood. Test resistance on whires and get 1200 ohms.

So I go and buy MSD 8.5mm superconductor wires and the arching goes away but its still missing. Wires are installed very clean with about 2 boxes of wire holders and definately not touching metal anywhere. Also the grease was used

Delteq is shipping out a new coil pack system and will be here tomorrow.

Is there Anything at all else that can cause a missfire?

 

clogged fuel injector, low compression, bad O2(if the PCM thinks it's rich/lean, it will pull/add fuel, and both can cause a misfire), bad PCM, open/shorted injector drive wires, ect

you need to narrow down which cylinder is misfiring, then narrow down what is not right in that cylinder

 

do you have any codes at all stored

 

Does it let out black smoke at WOT? What do the o2's hover around? It can be an excessive rich condition. Before my tune my car was so rich that my o2's were hovering around ~950-975 at idle and it let out black smoke at WOT. Made the idle rougher, and it would misfire and pop out of the exhaust like gunshots.

 

alright, a way to tell if its cylinder specific
1) get out a water bottle
2) set it to mist
3) have somebody get in the car, and stall it up to where it normally misses
4) mist each plug individually (on the block, not at the dist.)
when you get to one thats missing, it'll sputter really bad and want to die

warning: you MAY geta shock, and i am NOT responsible for you getting shocked, but this is one of the best methods i haev ever found for finding a miss

 

Delteq thinks it the #5 and 8 coil pack are arching internally. I will have it replaced tommorow and hopefully it solves the problem.

I have a feeling its the opti.

They need to make a cam sensor for the lt1 that can completely elimate the opti. Ide pay a crap ton for it.

 

Btw, no codes and no black smoke, although it does smell a little rich.

 

Gonna pick up a new o2 just in case. Will post results tomorrow with new O2 and new coil packs.

 

you could have an internal intake leak. check your vacuum.

 

found a vacuum leak and fixed it but made no difference. Gonna look over other vacumm hoses also becasue the first one i checked was leaking so I wouldnt be surprised to find other leaks.