Engine Stutter/cough on acceleration...is vp44 bad?

[dripley]

If you dont have a FP gauge you could get test maybe from an auto parts store and check it. 

[hdpwipmonkey]

Yep, looks to be a stock one.  Might want to go to the auto parts store and see if you can either purchase a pressure tester kit for fuel pressure or see if you can rent one.  It'd be good to see what your fuel pressure is at with that pump.  If its low then your VP is probably toast also.  Your VP pump needs the steady flow of fuel to keep cool if your lift pump goes out the VP will still be able to pull the fuel but there won't be enough to keep it running cool and it won't be long before it dies completely.

 

Don't worry about the questions.  They aren't stupid.  I had a lot of the same questions when I got my truck too.  This place helped me a lot over the last year or two.

 

 

Edited March 20, 2020 by hdpwipmonkey
dripley beat me to it...

[Zekeworst]

Also, I was just curious if the pump would prime so I tried bumping it to see if I could hear it prime and It didn’t. 

[dripley]

Pump mught have failed completely. Main reason mOst all of us have FP gauges.

A weak or failed lift pump=a failed or weakened VP.

 

You could put some 2 stroke oil in the fuel and see if that. Wally world is fine. TCW3 ashless is what you are looking for. 

Edited March 20, 2020 by dripley

[Dieselfuture]

40 minutes ago, Zekeworst said:

Damn owning a diesel is an expensive hobby... ?

Pretty much anything these days, unless it's a hammer or a pair of pliers 

[dripley]

44 minutes ago, Zekeworst said:

Also: I apologize for all of you who may think I’m asking “stupid” questions. I’ve never owned a diesel before and I’m just trying to make sure I can (hopefully) pass this truck on to my future child(ren). 
 

Yup. It’s stock. I see a mopar sticker on it. 

So... From what I’m gathering, I can either: 
A. Replace the lift and in tank pump and hope it fixes the problem

B. Replace the VP pump (which will most likely fix the problem 
C. Replace all of those components and KNOW it will fix the problem. Damn owning a diesel is an expensive hobby... ?
 

I also just noticed that there’s a slight crimp on the inlet side of that lift pump. That could be why it’s doing all of this. I’ll see if I can uncrimp it. 

A. You dont have both most likley. The in tank pump was a Dodge solution to the block mounted pump. They both suck.

B. Most likely. Test the existing lift pump pressure first.

C. Most any 20 year old vehicle can be expensive at times. Haevy duty vehicles can be pricier. 

[Tractorman]

24 minutes ago, Zekeworst said:

Also, I was just curious if the pump would prime so I tried bumping it to see if I could hear it prime and It didn’t.

 

That is a good test.  When you turn the key into the "run" position, the lift pump will run for about 1/2 second.  When you bump the starter, the lift pump will run for about 20 seconds.  Make sure the key is in the "off" position (key can be removed position) before you start the test or you may get erroneous results. 

 

If you are not hearing the lift pump run, the, check the condition of the fuse.  If it is blown, the pump may be faulty and drawing an excessive amount current.

 

If you are going to keep this truck, and it sounds like you are, then you should invest in a factory service repair manual for your year and model of truck. This manual will show the locations of all electrical grounds for inspection.  Or, you could become a member of this site and use the site's available resources, such as wiring diagrams.

 

- John

[Zekeworst]

Just checked the fuse. It’s good. Now my brake lights won’t work. I’ve checked the fuse on it, it’s good, and I’ve got power going all the way back to the socket. Now to test the switch... 

Edited March 20, 2020 by Zekeworst

[dripley]

49 minutes ago, Zekeworst said:

Just checked the fuse. It’s good. Now my brake lights won’t work. I’ve checked the fuse on it, it’s good, and I’ve got power going all the way back to the socket. Now to test the switch... 

Here is one that takes some getting used to. Most of the electrical system is negatively switched. You can have power to the socket and it still not work because the ground is not complete. You have probe the + and - in the socket.  I would have to defer to those more knowlegable to explain that though.

Help guys, a bit out of my league on this.

 

Edited March 20, 2020 by dripley

[Zekeworst]

Switch only has constant power (white wire) and the other connection on the four prong connector for the brake lights does not trip my test light. Turn signal and constant power work but the other wire doesn’t trip the test light. I’m at a loss. At this point it’s this kind of little sh!t that’s making me want to get rid of it. What bothers me the most is the fact that yesterday they were working just fine (and they have worked for the past 7 months since I got it) and now they just don’t work. 

Edited March 20, 2020 by Zekeworst

[Zekeworst]

So... Update on my truck. I haven’t been able to get anywhere in terms of checking fuel pressure. I recently moved (my old roommate upped the rent on me) and haven’t had the finances to do anything more with it. BUT... I was able to check all of the grounds (finally) and just recently (a couple days ago)I noticed that the lift pump FINALLY decided it wanted to start working again. By happenstance, when I turn the key to the run position, I heard it prime for about 30-45 seconds. If I bump the engine, it primes again for roughly that same amount of time. The stutter is still there. Yesterday when I drove it, it didn’t stutter at all. There was consistent power from both a dead and rolling stop. 

[Dieselfuture]

5 hours ago, Zekeworst said:

I heard it prime for about 30-45 seconds. If I bump the engine, it primes again for roughly that same amount of time.

Should only be a second on key on and 30 or whatever seconds on the key bump. Wonder if you don't have a timed relay in fuel pump harness. You could just check the ECM plug for voltage in both situations.

[Zekeworst]

2 hours ago, Dieselfuture said:

Should only be a second on key on and 30 or whatever seconds on the key bump. Wonder if you don't have a timed relay in fuel pump harness. You could just check the ECM plug for voltage in both situations.

Yes, you’re correct. It was late when I posted that and I was tired. I was falling asleep when I was typing it. It only runs for a short time when the key is on and after bumping it, it runs for awhile. 

[Dieselfuture]

3 hours ago, Zekeworst said:

I was falling asleep when I was typing it.

Little screen addiction can we say, 

[Zekeworst]

1 hour ago, Dieselfuture said:

Little screen addiction can we say, 

If you’d like to call it that. Lol I slept until about four in the afternoon which is why I was up so early. 

[JAG1]

On 5/14/2016 at 6:51 PM, dripley said:

Volt meter is low also. That could be part of the problem. How did you check the codes? Fuel filter good?

You got bad ground or bad positive side somewhere. If you watch even the oil pressure gauge coincides with the engine miss fire. Also possible low tank level gauge from a bad connection. Film shakes around a bit to tell much on the fuel gauge tho.

[Zekeworst]

I’ve decided to replace the VP44. She needs it badly. One other side tangent. I now have what seems to be low compression. The truck idles really rough (enough to shake the truck back and forth). There’s white smoke coming out from behind the ECM (on the side of the block) where the fuel filter is (I haven’t been able to isolate the leak yet). I’m wondering what kind of seal(s) could be down in that area and how easily they can be replaced. 

[dripley]

The factory lift pump was mounted just to the rear of the filter canister. If your pump has been removed/relocated there should be a metal plate in its place sealing a hole in the block. It could have come loose and be venting crank case gases.

[Haggar]

There is also the lifter gallery plate and seal.  It sounds like if you are doing the vp  go ahead and replace that gasket at the same time.

 

GL

Hag

[dripley]

Dug back in your and see you still have the factory lift pump. The mounting plate blocks the same hole and could leaking. Also the tappet cover, same as @Haggarmentions just a different name, could be the culprit too. Even if its not leaking change it while the VP is out. Much easier that way.