need some help . can anyone give me some info on why my oil cap would pop off on start . or while running . My truck died on me at 65 mph on the freeway . ended up towing it home . it lost all power and the oil cap popped off . now it wont start . and when it acts like its about to the oil cap shoots out . any info would be helpful .

 

Holed a piston.

What year truck, and what engine?

 

2004 2500 quad cab 4x4. 5.7 liter . guess its going back to the dealer lol . didnt want to hear that . i just bought it and it ran good during the test drive . had it less than 3 months . didnt get to drive it much . only put about 1200 miles on it . was driving fine before that . thaks for the info . ill call them tomorrow let them pick it up hahaha .

 

Was it making any strange noises?

 

it backfired once before it lost power then when i pulled over to the shoulder waited a few times tried to crank it it backfired again . then the battery drained . towed it home . i put my money down on the thing and dont have that much to put into it . .. charged the battery . oil cap still pops off .. i was kinda thinking the pcv valve . no one around here can steer me in the right direction . oil cap still pops off after about 3 rotations of the engine . flies about 20 ft or so after it hit the hood .. other than the backfire didnt get much else .

 

Yeah, something broke. You are getting compression into the crank case, and that will launch the oil cap quite a distance. That motor is just done. Any warranty on it?

 

Guess i got it from the wrong place . i can probably run a compression check on it tomorrow . but sounds like its done . as far as warranty guess i got screwed . guess ill find out more in the morning . i ve got the compression tools just they hiding from me lol . ill have to dig them out . since i worked out of town first two months only drove it a total of 6 days before today .

 

Please let us know what you find, and how things turn out.