If it were a valve issue, his compression numbers would be off. According to him though, compression test was fine, so, I suspect this is an electronic problem, not a mechanical one.

 

i pulled the valve cover off and have a fallen rocker on number 6.i dont know if that is the whole problem yet the lifter is froze up so im just gonna change them all.its confusing because the compression was between 152 and 166 for all 8 cylinders.thanks again for all the help i'll post when i know if that fixes it

 

That's pretty wild. Not the result I would expect....... There's one to keep in mind.

 

That's the same thing I though when this happened to my 2002. This happened to mine back way back before anyone one the internet had posted anything about dropped lifters except for one post from a guy on a mailing list who mentioned the exact same symptoms and that a rocker arm had fallen off.

I had already tested compression at this point and everything was perfectly fine with all cylinders so I was a bit stumped. I did notice that 2 cylinders did sound different while testing. That's when I found the post I mentioned above. I pulled the left valve cover and sure enough, two rocker arms had fallen off. I popped them back in with a wrench and fired it up. Problem resolved.

Since mine were exhaust valves, the truck was running horribly at all times because the exhaust had nowhere to go except into the intake when it opened to inject air/fuel.

What was really strange about mine is it didn't drop the rockers until about 12 hours later when I started the truck in the road. Since it overheated, I attribute this to that but I still don't know why they dropped so many hours after. Luckily the steel valve seats didn't drop out damaging the valves or pistons.

 

put in the lifters and put the rocker arm back on seems to have fixed it runs good now no miss.thanks for the help