Recently, my truck has started misfiring. At school today, we hooked it up to the Mac scanner to see what was wrong, and then after that told us pretty well nothing, we hooked up an older scanner to see if it could tell us much. We could never get the scanners to tell us which cylinder was having the misfire. Being that we can't tell which cylinder is misfiring, we are kinda at a loss for what to do.
Does anyone here have any ideas, or has this happened to anyone else? It's not fun having my truck running like crap, and I hate to drive it, but I have to drive it in order to get to school, thankfully its not too far from home, and to get to work.

 

You try changing the plugs/coils?

 

take it to auto zone and let them pull the code they should be able to tell you which cylinder. or replace all the plugs and wires

 

I would just replace all of the plugs first, see if that fixes it...It's cheap and should be done for norm maintenance anyway...If that doesn't work then move on to the wires...They aren't TOO bad to replace price-wise...Pray that it's one of those things...Esp if you haven't replaced it in a while/ever.

 

If you need replacement coils, Ive got 8 of them in a box ready to go.

 

NO, you do not just go ahead and replace the plugs, if they are not 30k old it would probably be wasted money. YOU PULL THE CODE FIRST, that is what the codes are for. Then you start troubleshooting and replacing parts...

 

The 30k is a myth. It is probably a bad spark plug due to the fact that you drive such short distances like myself. When you only drive your truck for a few miles and shut it off the spark plugs gather crap on them that over time short circuits them so no spark is crated because there is no more gap. The reason the spark plugs gather crap is because the spark plugs are self cleaning if run at a certain temp for a decent amount of time. ie highway trip to work (20 mins)

 

I pulled the codes, and it was a P0300 which just said cylinder misfire. I'm not sure off the top of my head, but the plugs and wires don't even have 10k miles on them, they have a bit less than that. I had all plugs and wires replaced when I had a tuneup done on my truck last spring break. I do drive short distances, but I try to take interstate home each night, which amounts to just a little driving, but still gets my truck up to higher cruising speeds and blows some of the cobwebs out for a few minutes, and then I also get to travel on some higher speed roads along the way. Nothing as far as major highway commute. Tomorrow we are going to pull the plugs and see if there is anything with those causing problems, but my teacher was thinking that it wouldn't just because of having two spark plugs, having both of them fail on me, but we still didn't rule that out completely.

 

Checking the plugs wouldnt be a bad thing but I would bet it is a coil that is giving you your problems. 10K miles on plugs and wires isn't enough to to have wore out plugs but stranger things have happened. And I think you could get a misfire with one bad plug due to the fact that one plug only fires on the waste fuel left in the cylinder. To bad you don't have a Tuner that would tell you the exact place of the misfire. Good luck with it and keep us up to date.

 

P0300 is a multiple cylinder misfire, meaning more than one experienced a misfire.

It's not going to be a single plug failure. A multiple cylinder failure can be anything from a simple vacuum leak in the intake manifold or throttle body to a defective EGR all the way up to a blown head gasket.