My truck was showing missfire on cylinder 6 so
replaced fuel injector. Then turned on truck ran
fine. Let it run a little then showed running lean and
miss fire on cylinders 7 and 8. Replaced fuel
injectors on those then showed miss fire again. I
replaced the spark plugs 4000 miles ago what is
Some things it could be: low fuel pressure, bad coils, bad ignition wiring, low compression, internal vacuum leak. Instead of throwing parts on it hoping to inadvertently fix the problem take it to your favorite shop and have it gone over.
Do what "tennisshoes" uh, GA says as it is real good advice.