Silverado engine swap now want start

[Justinwells14]

I have a 2001 silverado had a 4.8 changed the 4.8 to a 5.3 also used the 5.3 harness and ecu, want start; turns over fire it's like it fires off and dies, any help would be awesome.

[carriedi]

you didn't need to change the pcm and harness.

your going to need to go to the basics. check fuel pressure, injector pulse and spark. Is your passlock working correctly? if your truck uses anti-theft you will might need to do a relearn.

[Taylor25]

I have a 07 1500 Chevy Silverado LTZ 6.0 vortec max with about 130000 miles on it I've hade it for about 6 months and I've hade cylinders cola pse two diffrent times the 3 and the 6 I paid two grand for the first cylinder repair have not hade the second repaired and was wondering if it would be possible to swap the 6.0 vortec for a 5.7 vortec because the 6.0 just keeps giving me problems but I want to keep the truck please help me out here thanks

[carriedi]

what do you mean when you say the cylinders collapse? what did you have repaired the first time?

[Taylor25]

My lifter arm broke the first time I had it replaced then two months later it happened a second time but this time it was just stuck in place the mechanics shop told me it had something to do with my cylinders

[carriedi]

if it's just a rocker arm problem I would look at the engine oiling system for a problem. The rocker arms breaking or being a problem shouldn't be that expensive to repair. Much cheaper than replacing a motor. And they have had a pretty good record with the 6.0L