[Batman96LS]

well...i took the car to the garage today.  they billed me $163 for 3 hours of diagnostic work.  my ignition is excellent, plugs and wires excellent, compression excellent, no bad sensors, and my injectors are amazing.  he narrowed it down to bad gasoline.  he said run some injector cleaner and some heat in it and see if that helps.  stuck that in 3/4 of a tank and guess what...nothing.  it's still misfiring like mad.  so i got a bill for a ton of cash and got nothing in return for it.  i'm so pissed off.

[96mcls]

mine was running a little rough, and today i put premium in and it now runs smooth as glass

[Batman96LS]

i have little faith in the idea that 2 octane points are going to do any good at this point.  i am down one entire cylinder here.

[oleshifty]

maybe sometin to  check......when the o-rings around my valve cover holes went, the hot motor would let a lil oil slip onto plugs, and it would miss, but not real bad unless in  heavy traffic....... maybe sometin along those lines (i know its not a dohc, not sure what u got)

 

have u autotapped it?  thats only thing i can think of..... try  swappin wires, coils, plugs, maybe sometin u can't visually see is culprit.

[Germ]

i have/had the issues for some time now as well.

ive been tinkering with the idea that somehow the wiring for the coil packs may be compromised somehow. dont know how, but thats the only thing it could be.

i had some issues when i was N/A, nothing to noticable, even when i had the 3100. now with boost its amplified a little and seems worse.

i do have a bad injector, but that dosent explain why i had it with the 3100/3400.

i have personally changed

all 3 coils AND the mounting with it

wires

plugs (many times)

scanned the car (misfire on 6) whats weird about this one is that if i change the plug on 6 it does nothing, but if i change cyl 5, the idle and everything is fine for about a week, no noticable misfires. but if you look at the #'s on the lower intake, you will see that the cyl #'s are reverse to what the coilpacks go by. the inj's are #'d the same as the coil packs. so i was thinking that the pcm may read it different because when i mess w/ cyl 6 (according to the coil pack, inj.) then nothing happens, but mess with cyl 5 (according to the coil pack, inj {6 on the lower intake}) then the idle is good for a bit.

atap'd it, running slightly lean, 880-910 under wot.


you may want to go to another shop andrew

[MasterJacko96]

you think that you might need to consider upgrading the ignition to good coils like msd cause if i recal malcypse was haveing trouble with his stock gm coil packs as well. i would think with the boost your running it pust more of a strain on the ignition so i'm justr wondering if some good coild might help

[Batman96LS]

i recall it being checked in the past where MSD coils and stock coils are vitually identicle and there isn't any gain or much of a difference between the two.

at the shop they swapped plug wires to different cylidners...plugs to different cylinders...changed the coil packs around...virtually everything.  they found nothing wrong with anything.  he started it and it ran great.  then he shut it off and it ran horrible after that.

they checked the misfires with the scanner and it went from cylinder 2 to cylinder 3 which doesn't make sense because they aren't related on the coil packs and it is reverse flow on the fuel rail.  and when one cylinder dropped the other one picked back up.

the manifolds cross over the block so that's why they are reversly numbered.

the one guy that was lookin at it has had like...20 or 30 years of experience on the wrench and the other guy that was working on it is a master technician certified by gm and formerly worked at the chevy dealer.  these are literally the only people in town that i know that won't screw me.  i've known them most of my life.

i apreciate the ideas though.

[Batman96LS]

...and now...the car runs just fine...ses light is off and everything.

i started it up and it sounded like it had a HUGE vacuum leak.  so i checked the ball and pushed the hose on further.  pushed the hose on further on the vacuum modulator on the trans and the car now runs fine.  no clue...kinda confused.  maybe it was simply a vacuum issue...?

[MilzyZ34]

so it's all fixed now?

[Batman96LS]

dunno...hoping so.  i drove it around for a while after it smoothed out...beat it a little...loved it a little and the ses light has gone off and she seems to be running fine now.