Author Topic: '03 Dodge Cummins woes (Read 643 times)

azmtnman · « **on:** February 01, 2023, 09:05:44 PM »

On a trip back from Phoenix about 3 weeks ago, my truck popped an injector. After 3 weeks in a shop 200 miles away, I went and picked it up yesterday. Between there and what I drove it today was about 300 miles.
Anyway, after the injectors being replaced, I still had a hesitation in cooler weather when pulling hard so I replaced the fuel filter. It is an aftermarket, external fuel pump with a fuel filter and water seperator. I think it is an AirDog. After replacing the fuel filter, the pump wouldn't run!!! I thought I just wasn't hearing it so I started the truck. It ran for about 5 seconds and died. I have no 12 volt power to the pump.
It's an '03 HO (I think that motor was standard in '04) 24v with the electronic injectors.
Anybody got any ideas?

Mooseherder · « **Reply #1 on:** February 01, 2023, 09:46:47 PM »

Sounds like your lift pump.

barbender · « **Reply #2 on:** February 01, 2023, 09:49:20 PM »

Ha! I just came in from laying on the cold frozen Minnesota snow covered earth and dropping my tank to change my not very old fuel pump. The connector on the pump is slightly burned, and I have to do some figuring in the morning to see if I have a power/ground issue, or if the pump was just drawing too many amps.

I had tested power everywhere short of dropping the tank, and it was good. Then I get the tank out, put power to the pump and it runs🤦‍♂️

Here's part of the problem, and maybe something to do with what you are experiencing- the '03 Dodge Cummins was equipped with an electric inline pump that apparently had a high failure rate. They were updated to an in tank electric pump, so they had an external relay and power wire going back to the tank. In my case I may have corrosion somewhere causing issues.

In your case, I would find the relay first. They are tied into the positive post on the driver side battery. The power wire goes through an inline fuse (check it) to the relay, and then there are 3 other wires. I think they are power out, ground and signal from the ecm. The power out should come out of the relay and head behind the wheelwell. If you get under the cab, there is a connector behind the wheel well where you can check for power, and make sure it's not corroded.

I suspect I will be running a new power wire back to my pump in the morning, to eliminate that.

barbender · « **Reply #3 on:** February 01, 2023, 09:50:43 PM »

Also, you have to click the key into the run position, and I read that the ECM will only supply power to the pump for 30 seconds if the engine isn't running. So you have to click the key on and check for power fast.

azmtnman · « **Reply #4 on:** February 02, 2023, 08:42:11 AM »

Thanks barbender! I will check all that out today.
I hope you get yours fixed quickly.

tacks Y · « **Reply #5 on:** February 02, 2023, 08:45:09 AM »

What pump do you not have 12v to the air dog?

azmtnman · « **Reply #6 on:** February 02, 2023, 08:55:21 AM »

No 12 volt power to the pump.

HousewrightVA · « **Reply #7 on:** February 02, 2023, 08:58:20 AM »

Ditto on the connection at the positive battery post

moodnacreek · « **Reply #8 on:** February 02, 2023, 12:17:04 PM »

Electric fuel pumps. First let me state that I remember when Ford went to them just before efi. It was so bad that those who understood put the mechanical pumps back on. Replacing an in line pump with an in tank electric pump is going from bad to worse. Sadly mechanical pumps are not as reliable as they once where but I still like them. Electric lift pumps must be under the hood with a spare unit wired right there.

barbender · « **Reply #9 on:** February 02, 2023, 12:34:50 PM »

I'm with you on that, Moodna. I would reinstall an inline, but finding a way to cleanly install the draw straw etc. into the tank is turning into a project all of its own.

chevytaHOE5674 · « **Reply #10 on:** February 02, 2023, 12:43:51 PM »

Aftermarket sump (Beans Diesel is my go to), sawed and sealed into the bottom of the tank with an inline pump. Quick and easy to change when needed

barbender · « **Reply #11 on:** February 02, 2023, 01:28:14 PM »

I'll check into that, Chevy.

azmtnman · « **Reply #12 on:** February 02, 2023, 01:32:07 PM »

Quote from: barbender on February 02, 2023, 12:34:50 PM

I'm with you on that, Moodna. I would reinstall an inline, but finding a way to cleanly install the draw straw etc. into the tank is turning into a project all of its own.

I got it!!!

Turns out, the pump hasn't been running for the past 6-8 months and probably 10,000 miles. I always thought those engines REQUIRED positive pressure to the injector pump. Anyway, got the wiring problem (self created several months ago!!) figured out and it resolved the hesitation issue also.
Barbender, I like this AirDog setup. Looks like their about $750-800. Mine is mounted between the frame and the body outboard of the tank. The only other problem I've had with it is the bracket broke on me. It hung by the hoses and kept working until I discovered it and wiretied it back up until I could build a heavier duty bracket. The filters are the easiest filters I have to change. The wiring is super simple too. Wasn't hard to check everything once I had a diagram.

barbender · « **Reply #13 on:** February 02, 2023, 01:48:52 PM »

The VP44 (I think that's the model) will suck fuel, same pump is used on the LB7 Duramax with no lift pump at all. Talk about a fuel system that is prone to air leaks! Anyways, I think my Cummins was pulling fuel with the in tank pump basically turned off, causing symptoms of a restricted fuel filter. I changed the filter, and the fuel system won't prime because the pump isn't functioning. I'm still sitting on the couch trying to get the ambition to go out in the 0° cold and finish getting mine running😊

Forestry Forum
Sponsored by: