does anyone have a clue as to why my car dies after running for about 10-15 seconds?

it's a 94 Z28. parts inclue: hooker shorty headers, 26lbs injectors, bbk 52mm throttle body, msd opti-spark distributor, accel ignition box with coil, k&n cold air intake, and magnaflow exhaust w/o cats.

i bought the car a few years ago from a guy who didn't know anything about cars at all. the heads were blown, so i bought a rebuilt crate lt1 for it. after doing the engine swap, the car wouldn't start at all. i don't know much of anything about this style engine with all the electronics involved in it. i took it to a shop and the guy bypassed the aftermarket ignition box cause he said it was fried. the car runs now, but doesn't run well.

the previous owner never calibrated any of the aftermarket parts to the computer, so it runs nothing like it should. i am getting the computer calibrated this week. it ran rough when i first bought it, but didn't stall. i know the computer has to be calibrated still, but does anyone know why it keeps cutting itself off?

i'm completely lost with this. would really appreciate the help.

 

Is your check engine light on? Maybe you can check the codes for your problem.

 

sure sounds like the vats or security system is acting up. it could be the fuel pump relay or the computer is not seeing a motor running when it goes to closed loop so it shuts the injectors off.

 

Another vote for VATS. There are people selling VATS bypass kits for like $20. You can quickly eliminate or confirm that way

 

i appreciate all the info. one thing i forgot to write in the above post was it will stay running if i hold the throttle down to about 3000rpm as long as i want, but the second the throttle is let up even slightly, the engine dies instantly.

 

well thats a whole new deal. scan for codes test your map and maf and throttle positon sensor. be good to test your evap system as well. is it running rich? sure sounds like it could be. take a couple plugs out and see if there fouled. (black) how old are your 02 sesors? take one out and see if its fouled as well.

 

it's running very rich right now. the plugs are all blackened as well as the O2 sensors. i'm sure this is due to the oversized injectors. my evap canister is also making a "clank" sound sometimes when i turn the ignition on??? not too sure what that is, but i plan on replacing it asap. i've already had the car hooked up to the scan tool, and it reads no codes.

 

have a look at this, you can test your evap. both pressure control valve and purge solonoid valve were bad on mine.
https://camaroforums.com/forum/lt1-lt4-tech-9/testing-evap-system-51219/

 

thanks for all the advice on my car. turns out the opti went bad and so did the pcm. after replacing both, the car started right up for me. thanks for all the help though. i'm sure it'll come in useful in the future.