2011 RAM 1500 - Misfire

cylinder #5 misfire
coil replaced
fuel injector replaced
compression is good
what could be?

What engine ? Next choice would plugs . After that you would need someone good with a scanner .

The order in which this troubleshooting should have gone is…

Spark plug change first (cheapest item also)
Next… a swap of coil from a non misfiring cylinder (to see if the problem moved)
A new coil if needed
A new injector if there are clues to insufficient fueling

At least that is what I would have done in that order.

In your situation… you still havent ruled out that a simple spark plug isnt the culprit…and it very well may have been and still be.

I would also do the coil swap…because the other coils on cylinders with no misfire codes have functional coils and this fact is verified by your engine and ECU currently.

I hate to mention it but…sometimes new aftermarket components can be faulty right out of the gate…that is why I would not have swapped the coil so quickly… you may find that with a new spark plug, some di-electric grease and the OLD coil… You solve your issue.

But now that you have the info… I’m sure you get the idea. Let us know what you find out.