guys, know its been a while since i posted here, but i need some help because im now stumped.


truck was running fine up till a couple weeks ago.

between 1800 and 2000 rpm the truck would miss a little bit. noticeable and it wouldnt do it all the time. annoying. but no biggie right then. it started doing it more especially with a load behind the truck. finally threw a check engine code yesterday when i was towing my enclosed mow trailer.

threw
p0300 - random misfire
p0306 - cylinder 6 misfire
p0316 - misfire on start up

cleared the codes, truck still misfired a little bit, so i pulled the wire, checked it, seemed fine. pulled the plug to see if it was running rich or lean, looked alright. i also pulled plug on cylinder 5.. looked the same as 6 so i was like alright sweet fine, put the truck backtogether. runs worse than before. i drove it to the store to see if it would clear up. i could barely get up the hill to get to my road. went from 40 to 10 mph in no time flat, i would be able to pull that hill all day even with the original misfire.

plugs and wires are both only about a year old with 10k on them since replacement. plugs maybe a little more, but its been just over a year since i replaced the wires. dealer didnt do them both at the same tiem. so i changed the wires myself.

i feel like its too soon for wires, and why the hell would it be running worse after i took it apart and put it back together. i also cleaned the maf and still nothing.

thoughts on what to do next? i dont really want to get new wires and go through that hassle again. but if thats the only next logical step then ill do it. no rush, i have another truck to drive. just trying to see if there is anything else i can try before i replace the wires again.


edit: wont throw any codes either now. and it runs terrible. popping and missing and sputtering. wont idle straight either.

 

check the PCV hose for cracks/leaks.

mine was acting similar 6 months ago, turned out that one corner hose had failed. $6. to repair.

good luck

 

ah sweet. where would that be located? is that the vacum line that comes off the intake? i have a k&n and its just a ruber hose, not the factory plastic one. so theres a good chance it has a hole or something

 

on my 01' it runs along the passenger side valve cover. Didnt need to remove anything to get to it.
I can get a pic tomorrow if you cant find it on your own.

I was pretty sure there used to be a How-to here in this forum somewhere, I did a search & couldnt find it.
You might check around the internet, I'm sure you could find it somewhere.
Hopefully it will help your problem.
Good luck.

 

i havent had time to really mess with it, i have jury duty all week.. work all day friday. so itll be the weekend before i get to it. crappy part is ill have both trucks down tomorrow.. good thing im at court all day.

 

sounds like a vacuum leak. Get a thing of brake clean, starting fluid, or carb cleaner and spray around the vacuum lines and around your intake manifold. If you get a sudden increase in rpm your leak is in that area. I had a vacuum line give out one on the highway i went from 55mpg at a low rpm to 35mph with the engine screaming for dear life.