Need Help Please.. Installed a 96 motor in a 99 sho, now No Start

[Pitcher]

Hey guys I been searching like crazy for answers, but no luck.

Heres the scoop.

I bought a 99 sho with bad cams, I welded them up, and it ran, but the valves were bent. So I bought a low mileage 96 that ran great, but had a bad trans.

I pulled the subframe on both cars and swapped the good motor harness and all to my subframe.

Installed everything, and it will crank like crazy, but no start.

I am getting a rapidly flashing theft code which eventually produces a 16 code. I also do not have a SES light when I turn the key to on.

I also tried pulling DTC codes, but of course no connection could be established, probably due to the no SES light.

I have tried about everything, don't know where to go next.

Any and all help would be greatly appreciated.

Don

 

[kevinspann]

You kept the 99 PCM correct?

Edit: I don't know 100% if the harnesses are compatible across those years either. I'm thinking it's a PATS issue.

 

[Pitcher]

I have both complete cars and have tried both PCM's with no luck.

I also searched some more and found that the C130 plug above the trans has a few differences, and changed the pinout of the plug to match.

Still nothing, I really had hoped that I would atleast get the Check engine light to come on with the wiring changes.

I hope I didn't need to keep the 99 wiring harness and put it back on the 96 motor. That will not be fun now that it is in the car...

 

[Dubeckyj]

That may be exactly what you need to do. I remember needing to swap two wires from '96 to '97 during a vulcan engine swap on a SLO. '96 to '99 could be more dramatic.

 

[SHOMEX]

Well; hate to say it but thats what you need to do, you need to keep the harness from the 99 engine into the 96.

 

[Pitcher]

SHOMEX you were right, switched the harness's and all was good. Well except for a slight miss....

Thanks Guys!

 

[My_Silver_SHO]

Good to hear you got it running. With these cars its always something.