I have a 1997 F-250 it will drive fine for an hour or so then will lose rpms I can push the throttle to the floor and no response what so ever will only idle. I have a bank 1 too lean code and a P0300 random misfire I checked all the vacuum lines and they are fine. I can turn it off and start again will drive ok for 10 to 30 mins but gets worse as I go. . I have no clue what is wrong and neither does to dealer! PLEASE HELP!!!!

 

have they replaced the fuel filter? clogged fuel filter can trigger the random missfire code. may or may not help.

 

yes I. I changed it just last winter then did it again a few weeks ago but I was really dirty already. Could it be clogged again?

 

i would atleast check the filter you have now. has the fuel pump been checked for proper operating pressure? it has to be something specific to act the way that it does. damned gremlins runnin' loose again!

 

How would i check that? With a fuel pressure gauge?

 

When you have a bad hose you usually get P0171 and 174 together which you don't have. You have to look at bank 1 only for the lean DTC. You can check fuel pressure and volume, but again lack of fuel will cause problem on BOTH banks.

 

I checked my fuel pressure today it was 25 psi and was dropping. The spec call for 30 to 40 psi. Thinking its my fuel pump am I on the right track?

 

it was the fuel pump truck is running great

 

cool beans! glad to hear you found the problem.

 

Be sure u replace the fuel filter as well. I know u just replaced it but the old pump could have pumped some trash into it, this can cause your new pump to prematurely fail. I would defiantely spend another 10 bux and a little bit of effort to change it out, unless you have already done so....