well I'm driving along on the freeway on flat ground , cruising at about 60mph in my 06 while pulling a trailer and all of the sudden the engine starts making an awful rattle noise , kinda sounds like a loud pinging or detonation sound. at the same time the truck kinda looses power and starts shuddering. this goes on for maybe 6 seconds and then goes away totally and the truck seems fine again. then , a few minutes later it starts doing it again!. it then goes away just like before. then I start hearing a loud ocasional click or two here and there with a momentary engine stumble. anyway this comes and goes sometimes just a click or two with a momentary stumble, sometimes 5 or 6 seconds of missfiring and rattling. I continued to drive it for probably 100 miles sometimes with 10 minutes of perfect running inbetween incidents, just wanted to get the thing home. I wasn't doing anything different when it occurred , no hills or anything. doesn't show any check engine lights so I dont think it threw a code. the engine temp looked fine and the fuel rail pressure seemed to stay right where it always does. anyone have any idea what the heck it could be?? I'm afraid to drive it now but need it for work this weekend. any help would be greatly appreciated . as some f you may recall, I have already lost a motor at 18k miles in this truck due to a dropped valve. I am seriously considering trading this truck off on a gas rig or ?

 

Always start trouble shooting by reading codes!!!!
If you are asking me to give you an educated guess, I'd say injector issues.

 

can it throw a code without the check engine light coming on??

 

Yes, it can throw a code without the check engine light coming on, have taken mine in several times for different issues and even without the light coming on was told it had several new codes.