I have a 99 3500 dually 4X4. Driving it runs great all conditions however at highway speed, something clicks or cycles or??? totally looses power. I have to let off the acccelerator for 1-2 seconds and it will throw you back in the seat and runs so good again sometimes for 40-50 miles. I contacted a friend at cummins, little help. I am a heavy equipment mechanic so I also contacted a diesel pump shop. They are certain an injection pump, lift pump and filter will fix. I was thinking that maybe it was starving for fuel mommentarily so I changed the fuel filter tonight and there was metal filings in the housing and element. This is a dead give away has to be lift pump came apart. (PUMP ON ORDER), I read some other threads but not really definetive.Has anyone else had this???
Thanks Steve

 

WOW, I've read a lot but never heard of that. Your still pre LP and IP so where is the metal coming from?

Good luck

 

Yeah I had this when I had to change my first lp.... Replaced the lp and my truck ran like new... Depending how long ago your lp died, you may need to replace the ip... In my case mine lasted another 2 years.. Now to get gauges installed so as not to get to this point again..
Herold

 

Fuel filter is between the lift pump and the injection pump.


phox

 

I guess I should keep reading then. Or post so other newbs like me can learn from my mistakes

Question without hyjack shouldn't there be a fuel filter before the LP? Does that come with a in tank setup or aftermarket?

 

i wouldnt put a filter pre LP them sucker barely pumpas it is

 

Actually, I work for a power company. In 2003 I was assigned a "power joke" ( f-550). Everyone raved about them however brand new my f-550 would act like the old 6.2 chevy. At 800 miles I changed the fuel filter and it was like I hit the Gold Rush (brass) inside the ff housing. The Ford dealer replaced the lp and it ran 300% better,like itis supposed to ( but still not a Cummins.)

 

Momentery loss of power could be the APPS. I would try the reset before spending money for un-needed parts. It's free.

https://www.dieseltruckresource.com/...n&onlynewfaq=1

 

Thanks for the APPS link, will do. The Dodge dealer said there is a modification LP that now mounts in the fuel tank. Has anyone had feedback on the new "in the tank Lift Pump" ???

 

Do a search to find more info on the new in-tank pump. Most people don't like it, and some have replaced the old LP with after market pumps to keep from having to use it.

 

What one Dodge diesel tech told me is the lp is a pusher pump, designed to push fuel up from the tank rather than pull it, so in tank or near tank application is better. Another said locating near tank is better because away from heat of engine.

 

THIS WOULD HAVE TO BE TRUE. SEVERAL OTHER APPLICATIONS HAEV ADDRESSED THIS SAME ISSUE ( DIESEL AND GAS).

 

Wanted to add to this for what its worth. My truck was running without full power, not terrible but not what it should. LP checked out fine, but battery terminals were corroded. I took them off & cleaned them up, let it sit with only the negatives attached for about an hour, & now truck runs like new again. I would assumme all electrical components weren't getting enough fire (VP44, APPS, etc.), this procedure did work for me.

 

THANK YOU!!!! LP and filter fixed !!!!

 

glad to hear your truck is back up and running... now, get a fuel pressure gauge and monitor it closely to diagnose any further fuel problems.