licnep

Finished my build putting a AI 226/234 cam in my 96 Camaro. Open headers, nothing past the collectors. Stock tune while I wait for a pcmforless tune in the mail.

It started fine the first two days so I took it out for a small drive. Ran fune until it warmed up and would stall in drive unless i kept the revs up. If it died it wouldnt start unless I gave it a little gas. Anyway drove it home and let it sit for the night. Next morning I started it and again it started perfectly. The day after that I go to start it and it won't start. Turns over ok and backfires here and there, but nothing. Flooring it makes it spark a little more, but still no dice. I pulled the injector fuse to burn some gas out if its flooded and it still fires a bit (I'd even say better then when it's getting gas) but still nothing.

Any ideas on what could have happened? I've disconnected the battery for a few hours to clear the pcm, but that doesn't help. Could I have killed the o2 sensors? I have some flowmaster 10's on the collectors now for when it starts to keep the fresh air out, but this is driving me crazy.

Thanks for any ideas

SS RRR

iTrader: (2)

O2's aren't being used during cold start up, however what you describe with it running shitty after warming up could indeed be from O2's. So you're driving with a stock tune in it right now? I'm wondering if the PCM is wondering WTF is going on and dumping fuel? If it is backfiring it could be a timing issue. When you say it would "start fine" did it ever backfire? Is it backfiring during idle and acceleration or just deceleration? I would start by making completely sure the plug wires are in the correct locations. What method did you use to adjust the rockers and how much preload did you put on them?

HarleyZ28

iTrader: (2)

I wouldnt have even started it intill I got the mail in order tune.

96z28_lt1

iTrader: (3)

check for vaccuum leak? how about the opti..... needless to say after my head and cam build, my car started once... then wouldn't start after that chased down everything for ti to eventually be the opti, i guess the optical bearing spun itself? for it wasn't lined up right at all, old opti compared to new opti was like a 25 degree difference between the 2 with the cam pin at 6 o clock

licnep

Didn't know that lol. Yeah the car hasn't had anything but a stock tune yet, and I won't get my PCMFORLESS tune for another couple days. I guess yeah, the PCM must be dumping fuel because of how long it will continue to fire without the injectors. When it ran fine naw it didn't backfire at all. The backfiring I'm talking about is when I try and start it now. Like it will crank but thats when it backfires. Haven't got it to start since she stopped running.

Couple vids I took while she was running:

The very first start is
And it idling is
I've double checked all the vacuum lines and they all look good, no lose plugs anywhere either.

licnep

And as for adjusting the rocker arms I just felt where zero lash was, and when there just started to be a little resistance twisting the pushrod I gave it half a turn past that to set the preload.

1991camaro_rs

Right after we got the longtubes put on my wifes car the thing ran fine until we turned it off. Then it was a **** storm, backfiring, missing, could smell raw fuel. Got new o2's and fixed it, altho we didnt cam it it seems like what happened to her car. The day it went in for the 02's i would not stay running. I thought you could run on a stock tune with a cam swap, altho not advised. I would say get the tune in, and see if that works if not try o2's. Just my 2cents w/e thats worth.