Roach913

Wassup i have a 05 f150 5.4 and its been doing this for a while now let me explain ima try the best i can. Okay lets say im off to work i jumo in go to start and vroom its on. I now after work i go to start it and if you hold the key in the on position all you get is a long crank and never turn over. Somtimes when you go to start it you get a nasty grind noise as if the flywheel teeth were grinding with the starter that only happens once then you get the long crank but never turns over. Whats wierd is if you give it some time it will start right up like nothing. When this began it wasnt a big deal, it wouldnt happen often and if it did in like 15-20 it would start all i had to do was wait a little. Well now its even worse if i go out and try to start it odds are it wont start just crank and crank and crank till i let go of the key and now i have to wait hours before it wants to start. Whats even worse it went from just not starting to shuting off while im driving, somtimes as im stoped at a light it cuts off or somtimes in mid drive when i realese my foot of the gas for a little it cuts off them it begins with the starting problem. Its getting to the point that the other day a block from my house it shut off and i returned every hour and nothing untill the next day. I have taken it to a mechanic he said it was the computer and replaced it. It worked fine for a couple of days then bam it started doing its wierd things again. Took it back to him he replaced the cpu yet again and yet again the same thing. Right now its just sitting there not being used im afraid it will leave me stranded. The only code it is throwing is a p0455 code nothing else. Im tired of this problem and no one seems to know what it is. If you could help with some info that would be greatly appreciated. Again it starts when it feels like it and if it dont start it just cranks and cranks never turning over i can hear thr fuel pump click on aswell. Again if you wait some time it will eventually start like nothing happened.

nrivera04

Has the FPDM ,,,(fuel pump driver module) been inspected? You're describing some symptoms that point to a faulty one. Lower your spare tire and it's located on the cross member.

techrep

iTrader: (1)

Agree ^^^ inspect the FPDM.

Roach913

Ight will do apreciate the info. Thanks for the help good lookin ill check it out

tcp2

First choice is FPDM. Second would be evaporative purge valve. Video if for the 2009+,but can be an issue for a 2005 as well. More inline with the code you are getting. If it fails, it pulls a vacuum in the tank that can actually bow the walls of the tank inward and bend the sender.

https://www.rockauto.com/en/catalog/...+solenoid,4936

techrep

iTrader: (1)

A code p0455 most likely means one or more of the following has happened:

• A loose or improperly affixed gas cap
• A non-conforming gas cap (i.e. not factory/original brand)
• Other leak or damaged piece in EVAP system

WynnR2005

Hey guys can we come back to this for a sec? I have the same cranking noise and I did change BOTH recommended components. While changing these two parts helped other problems with the truck, I still get the cranking noise before starting. Any other ideas.

laterongc

you may want to start your own thread. Regardless (here or in new thread), try to clarify your symptoms, what codes you have/had, and parts your changed (and/or any test work results).

needsmoarturbo

Neither bad FPDM or evap valve will cause a crunching sound, they will just cause long crank or no starts.

If you have a crunching sound it's most likely a bad starter, but the next most likely is the flexplate could be damaged or broken.