My 5.4 just recently started starting hard, it cranks over twice as long as normaly. When im driving at 55 mph and step on the gas it will back fire and fall on its face and eventually take off. The check engine light came on once and flash a few times then went off i put it on a computer and it showed no codes. Anybody have any ideas to what my problem might be?

 

If the check engine light flashes then goes out the computer should have a code in it. Your scanner may not be able to read soft codes. May be a fuel related problem. How many miles on your vehicle?

 

It has 77000 on it i just put a new fuel pump in it in march so im i hope thats not the problem.

 

A fuel pressure check would show a weak or failing pump. If you can get a hold of another scanner see if you can pull up any pending codes. Have there been other problems in the vehicle history?