Rebuilt lq4, new bearings and rings. Has spark, fuel, and compression all I get is what sounds like popping in the intake. Tune is stock 6 liter with injector flownrates changed for the marine 8.1s. All grounds are good, battery ground on side of block and ground from harness then 3 on back of motor.

What do you guys think?

 

Tried extra pcm no change. Its like its turning backwards.

 

I've seen someone do this on a engine swap in a 1971 pickup....battery cables connected backwards on battery. No joke

 

They are hooked right visually, I might swap battery's and try it.

 

Timing chain installed correct? Piston at tdc, cam gear and crank gear dots pointing at each other?

 

Its all correct. Pulled the front end apart to double check.

 

Try removing pcv valve hose from the top if intake. Mine wouldn't start with it hooked up after i rebuilt it.

 

Mines hooked to a catchcan.

 

So its not hooked to the top of intake?

 

check the EVAP silonoied (poor spiling ) but you know what I mean