my 6.9 wont start

[straight pipes]

when i put a new motor in my truck ,when we got it all put together i went in to start it but it wouldnt start,it turned over fine but just wouldnt start,but when i put a gas rag on the breather it would fire right up.We took the injector pump off to see it it wasnt lined up but it was on the line up perfect.
i have tryied everything i have put a new pump on it,but still wont start.I can pull start it and it will fire up,but when i let it idle it has a low idle and when i get on it by putting the pedal to the floor it doesnt have the power like it should.So i have tried everything i can do to it but i ran out of ideas.

 

[sle2115]

Lift pump?

 

[aaklingler]

if you can pull start it i'd say batteries or starter. Are your gp's working?

 

[f-two-fiddy]

Did you rotate the engine with the IP off? If so, your IP gear could have jumped a tooth or two. Some say it can't with the gear cover on, but it can.

 

[Mr_Roboto]

Since it DOES run, just starts hard and runs bad, I agree with looking at the IP timing. It sounds like you already checked the timing gears, right?

Also, the scribed line on the IP is only correct for the factory original IP. Assuming that you are sure that the gears are lined up OK, try advancing the IP (rotating towards passenger side). If that gets it running better, then that was your problem. You should have the IP professionally timed at a shop and re-scribe your line.