2003 6.0 liter, fuel filter change, no start - Diesel Forum

paulgh · 10-20-2008, 07:36 PM

2003 6.0 liter diesel has been showing hesitation on throttle response. stalled the other day & would not restart, came back 3 hours later & started back up, then made it home, changed fuel filters (not bad), restarted & ran for 30 seconds then quit. Can't get it started again. Removed fuel tank & inspected, all ok. Removed filter & pump assembly, disassembled, completely cleaned, found heater corroded & disconnected it, then prefilled with deisel & reinstalled. When secondary filter cover is removed no fuel is being pumped up while cranking. What am I missing?. been working on this for several days, only got 1 error code, one time P-0670, could this being causing the no start. Sometimes it sounds like it wants to start, other times it just cranks over. Really could use some help!

hitecdan · 10-20-2008, 09:37 PM

Could be the fuel pump inside the HFCM is bad.

Page 29: Fuel Supply System

paulgh · 10-21-2008, 08:24 AM

Thank you. Not sure if i am getting power to the pump, when should I get power? When the key is on?, after cranking (oil pressure)? Is there a way to "bench test" the pump? 12 volts?

Would appreciate any additional input. Thanks

**LBraun** · 10-21-2008, 01:12 PM

The fuel pump turns on when you turn the ignition key to run. You should be able to hear the pump running.

The pump runs on 12 volts so it is possible to test it by providing temporary power to the pump.

Lou Braun

paulgh · 10-21-2008, 01:24 PM

Thank you, does it matter which side is + or -?

wdwkr · 10-21-2008, 05:04 PM

If the fuel filter in the HFCM is not seated correctly the fuel will not pass through to the engine mount filter. I learned this the hard way. I seat the filter into the cap until it snaps in and then install it into the HFCM.

dieseldiesel · 10-21-2008, 06:07 PM

The pump should run at key on for about 15 seconds then it will cut out. You should be able to hear it when you key on.

You can bench test the HFCM by applying 12V to the connector, the left pin is pos when looking into the connector and the tabs are oriented up.

You may have amplified the problem by disassembling it and re assembling without replacing the nitrile seals.

paulgh · 10-22-2008, 08:58 AM

Thank you, I checked and have 11.47 volts to the pump with the key on. When I disassembled the unit I did not take apart the pump itself, just the cover, filter & drain cover. I'll do a bench test next, just to make sure. The ford dealer has a pump, and reasonably priced, I just can not return it, so i want to make sure all my bases are covered.

OMCUSNR · 10-22-2008, 09:28 AM

Quote:

Originally Posted by paulgh

Thank you, I checked and have 11.47 volts to the pump with the key on. When I disassembled the unit I did not take apart the pump itself, just the cover, filter & drain cover. I'll do a bench test next, just to make sure. The ford dealer has a pump, and reasonably priced, I just can not return it, so i want to make sure all my bases are covered.

Paul,

If you took the drain cover off, you MUST use a new gasket. reusing the old one will not reseal.

OMC

paulgh · 10-22-2008, 05:49 PM

Installed the new fuel pump tonight. Bingo, the truck fired right up!

Thank you everyone who added their kernels of knowledge. I am truly appreciative of you taking the time to help a total stranger (with the exception of having a Ford in common) diagnose & repair their livelihood. I'm sure it saved me several hundred dollars at the shop.

Wishing you all the best,

Paul