trying to post this on LS Swap page

[1986brownjl]

Tried to post on lsx swap page but I can't find a "New Thread" button anywhere. But I having a problem with 2003 5.3 motor that I'm swapping into 85 k10. I'm trying to start the motor and let it run for a minute before installing it into the truck. I sent the PCM to brendan at lt1swap to flash it. Once I got it back I plugged in the wire harness and wired up the starter and PCM. And made sure all the ground wire are grounded. The engine will fire up for a split second then shut off. Anybody have idea what this might be or how to post on the lsx swap page. Thanks

[preciador6]

Make sure the key wire has power after it starts....if not hook up a ground to the engine straight to the battery,I had that problem it was my ground

[kwmech]

Fuel pressure? power to the pump after starting?

[mongocanfly]

All good points...they told me to ground mine every which way from sunday..battery to engine..engine to frame..frame to body..every combination you can think of..for my constant switch on power I used the big wire that went to the hei..you need a key on power and a constant power..fuel pump also..I'm assuming you already know all that.. does it die when you let off of the key or does it still run for a few seconds...do you have the maf installed in the intake tube..leave that out of the tube and it'll do exactly what your describing...if all this is done I would put a eye on fuel pressure and see what ya got.

[mongocanfly]

I just looked and the LS swap new thread button is still there on mine..if you don't have it you may need to reboot or something..

[1986brownjl]

Thanks yall. Right now I don't have it in the truck I'm trying to run it a little bit before putting it in the truck. Just trying to get it running good before putting it in the truck.

[qwik]

Check fuel press. first. Then start it with a test light in the injector plug and a timing light....divide and conquer, possibly a problem with the reflash imo.