possible trouble with injectors on Yukon

My son has a 2002 Yukon that`s developed a miss.It has 69k on it.I took it a friends and we hooked up a computer to it and it showed #5 cylinder missing.I swapped #3 & #5 plug wires and coils and put a new plug in #5 and the computer still shows #5 miss.Is this going to be a bad injector? If so how much trouble is it to change an injector on a 5.3?Thanks for any help!!

have you cleaned the throttle plate? I had similar type problem - a little miss not much. Cleaned the throttle plate and fixed the problem.

If you are in California I think there’s a special 10 year 200,000 mile warranty on the ejectors. Search for #5 cylinder missing under Suburban, Tahoe or C/K. I just read it early today. Try searching the work (Escondido). It’s a town in California that did this person work for free. Dave

My misfire problem on #7 and #2 ended up being a leak in the intake gasket. Local GMC dealer said it was due to a warped intake which seems to be common problem. Didn't believe them so pulled intake myself and had machine shop check it. Not warped. Intake bolts were not torqued to spec's causing leak at 45000 mi. New gaskets and problemed solved. Good luck