Dodge Cummins Diesel Forum banner

1 - 20 of 33 Posts

·
Registered
Joined
·
17 Posts
Discussion Starter #1
I have a 2002 Dodge Ram 3500 extended cab long bed 6 speed. I bought it this Monday and it had a p0216 code when I bought it. So I bit the bullet and drove it home. Luckily I made it all the way back. I had a KNOWN GOOD vp44 in my shop That I installed aswell as a Fass direct replacement pump on side of block with 3/8” hose. New cam sensor, tappet cover, rebuilt vacuum pump, new power steering pump and a wipe down later. I got it fired back up and went down the road. Only for it to buck and snort just like before. When I got back to the house it had a po216 code. Cleared the code. Installed new throttle position sensor. Same problem. I installed an ecm I had from same year model truck. Went for a drive. Same problem. Went to oreilleys and used their fuel pressure tester. It has 20-22 psi when I bump the key. 8-10 psi when idling. Gas it and it would drop to 0-2. So I put a new overflow valve on it. Drove it. Same problem. So I am stumped! I didn’t redo fuel pressure Test after new Overflow valve so idk if it changed or not. Anyone have any ideas?
 

·
Registered
Joined
·
19,380 Posts
I think your "known good VP44" was not so good.
 

·
Registered
Joined
·
274 Posts
I think before you go after the VP44, you should find out why you only have 0-2 PSI feed pressure when you 'gassing it'. Looks like there is a restriction of some kind. Fuel filter??
 

·
Registered
Joined
·
17 Posts
Discussion Starter #5
I think before you go after the VP44, you should find out why you only have 0-2 PSI feed pressure when you 'gassing it'. Looks like there is a restriction of some kind. Fuel filter??
I replaced the fuel filter aswell. Sorry forgot to add that into the list. I have another vp44 I can try on it and see if that fixes it. I pulled the vp44 off of a running and driving engine that had 172k miles. And sold the engine.
 

·
Registered
Joined
·
17 Posts
Discussion Starter #6
It had the exact same issue to a literal T on the stutter it’s having before changing parts. I’ve had a bad vp44 before and it stopped dead in its tracks. Locked the rotor up. But never had 2 in a row stutter and buck exactly the same. I’ll swap out the vp44 again if that’s my only option haha. I might try to get a fuel sumo and run 3/8” hose all the way to the Fass on the side of the block to help with flow.
 

·
Registered
Joined
·
52 Posts
Pretty fishy for 2 different VPs to act the exact same seeing as how VP failure can have several different symptoms and you said the donor VP was running. Definitely seems like you have a fuel issue with those pressure numbers, my FASS sits at 15-16 and drops to 14 on the gas.
 

·
Registered
Joined
·
17 Posts
Discussion Starter #8
Pretty fishy for 2 different VPs to act the exact same seeing as how VP failure can have several different symptoms and you said the donor VP was running. Definitely seems like you have a fuel issue with those pressure numbers, my FASS sits at 15-16 and drops to 14 on the gas.
Is it one of the direct replacement pump? On the side of the block?
 

·
Registered
Joined
·
52 Posts
Is it one of the direct replacement pump? On the side of the block?
No, mine is a stand-alone pump, but the pressure would still hold the same regardless of the direct replacement or standalone. You have a fuel delivery issue.
 

·
Registered
Joined
·
17 Posts
Discussion Starter #10
No, mine is a stand-alone pump, but the pressure would still hold the same regardless of the direct replacement or standalone. You have a fuel delivery issue.
I will order a fuel sump and 3/8” hose to hook to the factory replacement pump. See if that helps. If not I’ll replace the vp next week sometime
 

·
Registered
Joined
·
17 Posts
Discussion Starter #11
I should probably add that the truck is a 6 speed and I put a SO pump back on it. I’ve done this before on an 01 with great results and it made good power. So I didn’t think anything of it when I swapped it
 

·
Registered
Joined
·
19,380 Posts
He is right. Missed that with 2lb. That low may be your issue and or the cause of bad VP44's
 

·
Registered
Joined
·
19,380 Posts
Can the lift pump be warrantied? But yes you need one and a vp44. In recent years many lift pump brands are proven to been not so great with a lot of recent failures. No need to over do it , that can actually cause problems. Just quality operating in the 15-20 lb range with not more than 2-3 lb drop at WOT.
 

·
Registered
Joined
·
52 Posts
Maybe someone else can chime in here that may have this pump but its true that new aftermarket lift pumps are not what the old ones used to be. If my truck didnt come with an older FASS system, I would check out the predator mechanical belt driven pump from power driven diesel. Heres a link:
 

·
Registered
Joined
·
268 Posts
Curious, was the original lift pump that you replaced on the block? Or did it have the retofit where Dodge put it in the tank?
 

·
Registered
Joined
·
274 Posts
Good thought, Maxwedge. If the external pump (on the block) is added along with a failed in-tank pump, this is exactly what kind of fuel pressures I would expect. It's very difficult to get much flow through a non-working positive-displacement pump. Some pressure would show at the on-block pump output, but any load on the pump (engine starts) would drop the output way down because of the restriction of the in-tank pump.
 

·
Registered
Joined
·
45 Posts
I have had an AirDog 150 not the 4g for 3 years know and have no complaints about it at all 20 at idle 17 at 65 to 70 MPH probably 14 wot still running stock filter
 

·
Registered
Joined
·
268 Posts
Good thought, Maxwedge. If the external pump (on the block) is added along with a failed in-tank pump, this is exactly what kind of fuel pressures I would expect. It's very difficult to get much flow through a non-working positive-displacement pump. Some pressure would show at the on-block pump output, but any load on the pump (engine starts) would drop the output way down because of the restriction of the in-tank pump.
Sounds like he replaced a block mounted pump but who knows, it's not 100% clear.
 

·
Registered
Joined
·
17 Posts
Discussion Starter #20
I replaced a block mounted factory lift pump with the Fass drp pump. It shows manufacture date of 2010 on the new Fass DRP pump. I have no knowledge of an in tank pump. And the pump is still block mounted. I just installed a GDP Mk-10 I had in my storage unit with new filter and 3/8” lines all the way from Fass to vp44. Same issue as before. Like I said before I have another vp44. I will order an Airdog or might consider that predator pump. And install the fuel sump I have. I have drive the truck around the “block” total of about 7 miles. After changing map sensor, fuel filter housing, fuel lines, fuel filter, overflow valve. And it is still doing the exact same as before. But I have not gotten it to show a p0216 code in those 7 new miles. When I first put vp44 and still has stock canister it would show it but now it will not throw a code.
 
1 - 20 of 33 Posts
Top