So the story is that I had an 07 LS2 from a Vette. Bought the GMPP LS2 engine controller kit and it worked just fine. That LS2 is gone now and I have an LS3 from a 2010 Camaro SS. The engine cranks but wont turn over. The map sensor has been repinned to support the LS3 intake manifold. Everything else plugs right in. Other than needing a tune if it does fire up I don't see why it's not starting. Am I missing something here? Any idea why the car wont start? Thanks guys.

P.S. The car is a 94 Mazda RX7.

I'm just trying to rule everything out. There is fuel and there is spark.

 

If the GMPP ECM worked with the LS2 it should work with the LS3. The MAP sensor though has different pins as you fixed up and it also is 1.5bar so the tune really needs this fixed. It should still start though.

The LS3 from a totalled Camaro? Maybe one of the sensors took a hit in the accident. Running a MAF?

 

Yah the GMPP control kit came with a LS2/LS7 style MAF. It's on there.