I have an 03 blazer xtreme with 153k on it that im having problems with a misfire code, ive come to fact that the piston rings are bad in that cylinder and rather then trying to tear the engine apart to fix it and possibly find other problems i was gonna put a used engine it but im having trouble trying to find out what year engines i can use. I work at dealer and found a 4.3L from a fullsize '06 pickup with 50k miles on it but im not sure since it came out of a full size truck if all the stuff are same like the wiring and all the sensors and what not. If anyone can give me advice i would greatly appreciate it.

 

Odds are that everything will cross over just fine if you are using all your old sensors. How do you know one of those isn't causing your misfire though?

 

Ive checked everything, and then did a compression test on that cylinder and its low compared to all others and if you squirt oil in the cylinder the compression comes back up. So the rings are bad in that cylinder. So for the same amount of money id spend to tear the engine done and rebuild it, ive found an 06 engine with 50k on it from a 1500 at a junkyard.