my 98 ram shows a cylinder 4 misfire. It was quite noticeable when i first start it up and it shakes but once its warmed up it doesnt seem quite as bad. I replaced the plugs, wires, cap and rotor still the same problem. I used 2 bottles of fuel injector cleaner also. Nothing made a difference. As a last ditch effort i even replaced the #4 injector with one from a 318 ( i know these are probably different but wanted to see if there was a difference in how it ran and if it was completely blocked) Also i didnt want to throw money at it for new injectors when i had the 318 injector just laying around. The only thing i can think to do now is a compression test. any other ideas?

 

Start with the compression test because you need to evaluate the engine's condition anyway. After that, perform a leak down test on your #4 to see if it's leaking and if so, where it's leaking.

 

how do i perform a leak down test?

 

I posted a procedure on this thread:

https://dodgeforum.com/forum/2nd-gen...misfire-6.html

 

alright i will see what i can do, right now i'm away from my truck but when i get back in town i'll do the tests.