I know this is a common post, but I was driving home the other day in my 03 Ram 2500, Diesel, Automatic when I noticed that I had no power when I would step on the throttle. I was already at "highway speed" and the truck would surge when I hit the pedal, especially coming up a small grade when it would put a load on the engine. From a dead stop, it would sputter up to a point, but if I kept my foot out of it, it would level off somewhat smoothly. To me, it definitely seemed to be running lean like it was starving for fuel and doesn't sound like it normally does. I know the stock lift pumps in these are junk and I've got 80,000 miles on mine. The fuel I'm using and the fuel filter are fine, I've checked the filter and I put about 2/3 of a tank of new fuel in after this happened. I did a quick check of my fuel lines and injector lines and they appear fine. I got the truck home and have had it parked in the driveway since because I don't want to chance damaging the CP3. How much pressure should I have at the fuel line that feeds my injection pump? Is that the best place to test the lift pump? Any other suggestions or possible cause? Thanks.

 

You should have 12 - 15 psi at the CP3 inlet.

This sounds more like an APPS of FCA problem though vice a lift pump issue.

A bad lift pump will cause a hard start / no start condition, but the APPS and FCA will cause what you're describing.

The other item it could be is the relief valve on th fuel rail. Only way to verify these ACCURATELY is to hook it up the DRBIII and look at the numbers for these 3 items.

 

Thanks for the advice coal train. I don't have any codes showing, shouldn't the Fuel Control Actuator produce a code? What about pulling it off and cleaning it up? I know there is a way to check codes on the dash, but how? Any specific codes I should be looking for? If it was the Accelerator Pedal Position Sensor, would it act the same way if I tried to accelerate using my cruise control accelerate on the steering wheel? Sorry for all of the questions, this truck has been like my baby for the last 7 years and I just want to get her running good again.

 

If it is the APPS and you use the cruise control to accelerate, it may not work correctly because your cruise control still uses the APPS for it's signal. The ECM uses the signal to actuate the cruise control motor.

The fuel control actuator MAY produce a code, not always. If it's an electrical failure, it will. If it's a mechanical failure, it may not. Easiest way to check the FCA is to remove it (2 bolts and the connector) and shake it back and forth. You should hear it click. If you don't hear it click, then it's stuck.

You can pull it off and clean it, but most of the time this only buys you a little extra time until it just fails altogether. Usually it needs to be replaced.

Honestly though, the fastest (and cheapest) way to diagnose it is at the dealer. All they need to do is hook up the DRBIII and see what's going on. Shouldn't cost more than a $65 diagnostic fee and you'd know what it really needs rather than guessing at possible causes.

 

Well Coal Train I was getting ready to take your advice. I had an appt. scheduled for tomorrow to have the truck hooked up to the DRBIII to see what was going on with my rail pressure. However, when I went out tonight to start it up, the truck started right up and then died. I started easily a few times and then it went into the long/hard start. I have to believe that the lift pump is gone at this point. I still may have an FCA issue. I will know more in the morning when I look in the fuel filter canister. I suspect that I will find an empty canister. Any other thoughts?

 

Yeah, if you're getting a hard start, more than likely that lift pump is shot.

With the '03 you have that engine mounted lift pump and those are known to take a dump.

One way you can check it is to put a jug or bucket under the filter canister and open the drain ****.

Turn the key to run and then bump the starter for a second. This will cause the pump to cycle for 20 seconds. If nothing or little flows, you can be pretty sure it's the pump.

 

Opened up the drain to the filter canister and tried to cycle the pump. Nothing even came out. I opened up the filter canister and it was only about 1/3 full. I also got the P0628 (low voltage detected at the lift pump) code. I called the dealership to see if they would cover it, but they told me it wasn't covered under the Cummins Warranty. No big deal, I don't know if I wanted the in tank pump anyway. I ordered a FASS and will have it next week. I hope thats all that was causing my original problem of the truck running lean and sputtering under a load.

 

Shoulda gave me a holler brother and we likely could have saved ya some bucks......

 

Coal Train, what you got? The place I ordered the pump from called me and said that they are on back order for at least a week. I haven't paid for the system yet. If you have a good lead let me know. Thanks.

 

I'm assuming you want a FASS 150, the heavy duty series, right?

I've got 3 on-hand, ready to ship, p/n HD D08 150G.

I'll send ya a PM.