V1 Need help fast if possible

[MotoX2003]

So I’m being kicked out of my father in-laws garage today and would love to have my car running again. Quick story built it everything worked ran amazing decided to try and put a 2.0 sc in it didn’t work out wanted to keep driving it so I put the 2.2 back in. Now only the security light comes on briefly then goes out unless I use a wire to jump the run/crank relay then everything comes on and does it’s job and the car will run. I’m very confused and would love some help! Thanks so much!!

 

[Rttoys]

Not a whole lot to go on. Since you pulled out the engine and put another one in and back, I would check connections and grounds at the fuse box and such. Also, maybe relearn the key to see if that has anything to do with it.

 

[MotoX2003]

Not a whole lot to go on. Since you pulled out the engine and put another one in and back, I would check connections and grounds at the fuse box and such. Also, maybe relearn the key to see if that has anything to do with it.

Thanks I checked all the wiring that I could and everything seems good. What sends power to the relay for the run crank? Because if that would send the signal everything would work.

 

[escapepilot]

When you swapped to the 2.0, did you swap ecm and bcm? That may cause a key issue but honestly just guessing. I had a no crank after several good starts and it turned out to be a ground issue. I ran a heavy cable from trans to chassis and solved that issue.

 

[Ross]

I had that issue... would only start by jumping the starter, but would run after that.
Turned out the data wasn't flowing on the GM high speed LAN. A new power steering unit ended up allowing the data to flow, and my issue was solved... but the GM LAN does go thru other devices, that could potentially be the issue.

 

[Goblinfanclub1234]

can this be related to the ignition/key anti theft system? Do you have a different ignition and key than came with that engine?