P0300 - is there anyway to figure out which cyclender is misfireing, those coil packs are 80 bucks and theres 8 of them

Question

just trying to determine wich system is misfireing there are 8 plugs, 8 wires and 8 coil packs. i, all for working on my own stuff but im not made of money here. the truck has 250,000 miles and i relize they all probly need to be replaced, but at 80 bucks a pop i cant replace them all. any help is greatly appreciated.

Answer 1

What you can do is this:

With the engine running, unplug a coil. If the engine stumbles or runs rougher, plug it back in and go to the next coil. When you get to the one that doesn't affect the engine, that's the cylider with the problem. It's a very simple quick way to pin point the problem cylinder. Then swap the coil with the one next to it. If the misfire moves with the coil, replace the coil. If not, then the coil isn't the problem.