Oh, and don't reset the computer, when you fix it it will reset itself. It may take 20 miles (or sooner) but when that light goes out you know you fixed the problem. Sometimes reseting gives you false hopes.

 

yeah we are just gonna have to take it to my buddies shop so they can run a full diagnostic on the fuel and everything...my dad dosent want to keep dumping money into it if we arent sure whats the problem..but thanks for all the help guys! oh and the plugs and wires were a horrible experience haha.

 

The P300 code was thrown on my one (1) broken valve spring ( a few years back) and the truck ran exactly the same way. Also, check the resistance of the coil packs on the primary and compression test. Ironically, I am going through the same exact problem as you are now...again. Good luck with your dad's truck.

 

thanks firefighter...the only reason i would think it was a valve spring would be because it runs quiet...if the spring was broken wouldnt it make some sort of noice when it runs? i am gonna drop it off at my buddies shop tomarrow and i will mention what you said to him..could be a bad coil too..was your problem intermittant?

 

Welcome. Yes, it's the '03 that had the major problem with springs...it's just a thought. This is how my truck ran:

I'm cruising up the highway, 65-70, get on the gas a little and the whole truck shudders, like a flat tire. When stopped, it would hardly hold an idle and hover in the 500RPM range and sounded like sh**. On the outside sounded like a complete plugged cat. Did you notice any out of the ordinary moisture coming from the tailpipe? I had that as well.

I would def. do a compression check 1st and while pulling the coils, take a multimeter and put it across the two primary terminals. You should get between 0.5 to 0.8 ohms, anything out of that range replace. There are no published resistance readings for the secondary. All mine read 0.8. During my 1st broken spring I went ahead and changed all plug wires while I was in there.

How as it running just at an idle vs a higher RPM?

Update us on what you find.

 

I found a short video I took during the 1st valve spring break before I knew what it was. Here I am doing a vaccum test. The 1st 3 sec the truck is at an idle (about 500 rpm and struggling to stay alive), then I eased into the gas peddle and when I got around 2000RPM it would smooth out somewhat....then I let off completley and it drops back down to the 500 RPM range. Kinda hard to hear but if you really listen you can basically hear how it was running. Is your dad's acting similiar?

Hopefully, I can post a video here, guess we'll see if it works, it's on photobucket.

http://s318.photobucket.com/albums/m...geValve_02.flv

 

thanks firefighter...when idling in park it idols fine..its only when the truck stops in drive does it start acting weird and idling rough..it dosent idle as bad as our video tho..gonna take it to my buddies shop tomarrow will let you know the outcome. thanks for all the help!

 

atvkid4eva....how did everything turn out? What did you find out on your dad's truck? Give us an update....hope it all turned out well.