I have a 96 maf 4.9 that I think popped the head gasket. Losing water into the oil, engine stuck from sitting. I bought a freshly rebuilt sd efi 4.9 from a buddy who had removed the air injection and other stuff. I’m trying to swap all the stuff on to the new engine from mine but a lot of stuff is stubborn and twisting off. I assume I need all the emissions stuff in place in order for it to run properly and with no check engine light. Am I right?

 

You need the EGR system but not the air injection. Does the truck have the original cat still and does it need to pass a visual smog test?

 

Yeah it has the original exhaust, but it doesn’t need to pass a smog check.