well, today i finished the installation of my new engine. about 15 minutes ago, i cranked her over. it fired right up with a rough idle and died the next couple seconds. it keeps doing this. i got one backfire through the carb. i have a 1988 carb 5.7 trans am. used to be a tbi 5.0. is this a timing issue. i have it set at zero i believe. thanks for your time

 

use to have the same problem it would start right up then die, turned out there was something up with the carb, got it rebuilt and all was fine. check the carb out make sure everything is working good.

 

its a brand new carb though

 

What type of distributor are you using?
Do you know if the valve lash is set properly?
Don't take this as an insult, but are all your plug wires on right, etc.
Most of the time it is a simple yet very elusive problem.

 

Right, as Rusty said most of the time it's a simple problem.

However, never, ever assume that because something is new it's going to work right, and then eliminate it from the list of possible problems. I used to work at an auto parts store and I can't tell you how many times people brought defective parts back.. I can't tell you how many times I have gotten a defective part.

 

Yep, run through the valves again, sounds like one is overtightened.

Can be one of the other probs though...

 

would someone be able to tell me how to set the valve lash? also, when putting the wires on the dist. they go in a clockwise fashion with the firing order?

 

proform hei with an incap coil

 

timing, valve lash, plug wires, or a vaccum leak is what i think it may be, what else?

 

well, i just got home and decided to check my spark plug wires. turns out the 6 & 8 were switched . ill have to try it tomorrow at 6 when i get home from work, too late for open headers.