KFK

iTrader: (9)

I'll try to make this as short as possible. 00 vette heads, cam, bolt ons, 200+ miles since mods and tuned by rep. shop. Yesterday pulled out of store, got on it, then started to fall on face.

Symtoms since then:
1 idles crappy and dies
2 cylinders 3,5,7 seem not to be firing
3 no codes but dash says column lock and pull key wait 10 sec most times
4 undriveable

Things checked:
plugs, wires, coils, valve springs, push rods, cat. convertors, injectors

All help is appreciated, this is not my car, it's a buddys that lives 100 miles away and its stuck in my garage.

V-seriesTech

iTrader: (5)

Since you said 3,5,7,..all on the drivers side,..something tells me it's either a ground(back of cylinder head),...or the coil's/harness themselves. You said you tried coils/plugs/wires/ already. So, check that ground now. Service colum lock? Hmm....saw that on mine the other day and it was mostly due to a low voltage issue. Check the battery power as well, just for the hell of it. I've seen plenty of customer car have strange issue, you'd think not voltage related,...end up being voltage related.

I would have siad valve springs but, you already checked that. Does any one cylinder show more misfires then the others? That one MAY be the cause, and the other two are just following. If you can get it to idle,..start by pulling a plug off, one by one, see what happens with the idle.

You cuold also have a vaccum leak,...he can also have an 02 sensor problem if it's effecting driveability. Maybe a melted 02 wire? Check and see how those are sweeping.

Other then..does the car have any other codes? If not, or hell, if soo, write them down, and see if the car can be retuned(if not,..remove the battery cables and put them together, for 15-20 seconds,...then put them back on the battery terminals. Start car? Anything better? anything worse?


Also check for a break in the intake line, after the MAF

KFK

iTrader: (9)

V- thanks for your help. we checked the coils by switching them bank to bank and the issue stayed at the same cylinders. The car has set no codes but I am leaning more and more toward a ground issue due to the multiple problems.

Steve01SS

iTrader: (43)

Yeah a bad O2 "can" cause a "fake" misfire. If the codes are turned off in the tune, you wont even know if you unplug it. Except it will run like crap. I would check them, and yeah if you have access to a scanner see if the readings are not just locked to a voltage, this would indicate an O2 failure or problem

Cole Train

iTrader: (30)

i'm wondering if the grounds at the back of the drivers side head are loose.