We swapped in a 6.0 LY6 from a 2008 2500 Suburban into a monte carlo using painless wiring harness. Motor turns but does not start. We disabled VATS. It is a running a 2008 computer 5.3 LMG. PCM is using service #12612384. Heres is the tune..
It does have crank rpm cam signal and we also have spark. MAP sensor is from stock LS3.
Any ideas?