It just dies

[rxl]

No one ever encountered this problem?
Recap. Launch from the lights, it dies. Shuts right down.
Burn out and it stays running.
Launch on the gravel and it stays running.
This seems to happen easier when the engine is cold.
And the dealer scan came up empty. I keep thinking something with the fuel tank because it only acts up with sudden forward motion.
Anymore thoughts?? Everyone I talk to is stumped.

[mudseeker]

Originally Posted by rxl

Leaky exhaust manifold. Would an o2 trying to compensate for the leak cause this??

yes! your sensor is reading all the fresh air from the leak and adding more fuel because it thinks the engine is running lean.

[hotrodpc]

I understand what you are saying Mud, but my thought would be that fresh air can not be drawn into the exhaust leak for the O2 to read. Of course it will not be reading tottally perfect since some of the air is leaking out and not getting to the O2 to be read. Just saying, I am sure it can affect the performance, just not so sure its the fix for this problem. It would sure be cool if it is though. But it does sound to reason too being that take off from lights it dies, jump on it and it goes fine, so it likely is dumping to much fuel at light throttle take offs.

[mudseeker]

only way to find out is to read the o2 data. i bet it will show a lean condition.

[hotrodpc]

Yep, that I do agree with, because some of the exhaust gases are escaping thru the leak and not being read by the O2 sensor.

[rxl]

Originally Posted by hotrodpc

But it does sound to reason too being that take off from lights it dies, jump on it and it goes fine, so it likely is dumping to much fuel at light throttle take offs.

Jumping on it from the lights it dies.
Taking off normal it's fine.
Standing on the brakes and smoking them it's fine
And jumping on it on gravel it's fine.
Only the sudden launch from the lights on pavement makes it react. This is the symptom that keeps making me think about the gas tank.
It seems the pavement launch jars something. The only thing I can think of that moves during a hard launch is fuel in the tank.

[rxl]

Replaced the exhaust from the manifolds back tonight. Still dying.
Tank is next on my hit list but I'd like to relocate the tank to the rear where the spare is. Any ideas for a tank? Any common swaps for this?

[hotrodpc]

My best suggestion for that, would be to check out the measurements and location for a Suburban tank. If it fits back there, that will give you some mega capacity too. I think those are almost 40 gallon or 42 gallon tanks.

[hotrodpc]

But wait a minute, why do you just keep throwing good money after bad? I would not replace the tank unless you knew for certain it is the problem. If anything, but just because, take the tank to a radiator shop and have them boil it out and clean it for you. Probably $40 or so. Any body around you that you know have a sniffer for the tailpipe emissions? Find out if you are running a rich or lean condition. Its old school technology these days, but really, you have a wierd problem that has alot of us stumpped, and hate to see you spending your kids inheritance on something that is not needed.

[rxl]

No worries there. I'm wayyyy to cheap to waste money chasin ghosts.
No real $$ invested yet other than the exhaust, and it needed it.
I see rust around the filler opening and I'm 99% sure the tank has never been dropped. I got a stack of paper work 4 feet high with the truck. Even every gas reciept came with it. So ya, contamination may be my only issue here.
I'll check into the burbun tank. There's one in the tranny donator.
Not even sure why I want to move it other than wieght distribution. I lift everything else I own and I'm figuring on dropping this one and maybe adding a few ponnies. Little more wieght over the rear rubber cant hurt.

Thanks for all the advice so far folks.