Engine/Transmission (1998.5 - 2002) Just about to replace my VP44, but STOP!! WAIT!!

[RobbyRam]

My new VP44 has been purchased, however, a close friend visiting from El Paso, Texas, told me to HALT! Why, I asked? My symtom is 'hard starting' when warm. (after a new 4th lift pump replacement). He is up here in Sacramento to have his 3rd DTT transmission rebuilt, (not DTT's fault-he drags races in the southwest ) Anyway, he's also on his third VP44 injection pump, (Drag racing) he said but none of his injection pump failures matched my symptom of hard starting when warm only.



He advised me to wait 10 seconds before 'turning the key fully to start' even if the 'wait to start' light' goes out after 3 seconds. He thinks, and, now after several warm starts I agree, that my new 15 psi at idle lift pump is providing too much pressure at start, which has been causing my 'hard to start when warm' problems! What do you think? My truck still runs perfect when driving and in cold start situations.



Even though I am contemplating installing my new VP44 injection pump next weekend, I think I'll just wait a few days to try this 'wait to start 10 seconds' stuff first. After all, what can it hurt?



Even 'HVAC' told me that in warm temps. the VP44 doesn't like the too high of lift pump pressures.

Bob in Sacramento



PS. A local independent, but highly recommended Diesel repair shop here in Sacto is too 'booked up' with VP44 replacements to schedule me in until September, even though I have my own NEW pump. What is informative is that all of the R & R's have Power Edge Comps installed like me, FWIW!

Live and learn, I suppose



PSS. My Dodge dealer wants $3k to install the new pump with no guarantee.

 

[parcher]

Does the dealer really want 3k to installl YOUR pump or is that the price with them providing the pump?

 

[Ncostello]

My lift pump cycles for two seconds on key up. I'll sometimes see 16. 5 psi... but always above 15psi in this short time. As soon as it shuts off... I start it and it does perfectly. I always wait for it to shut off... always have. Just habit. Even when fully warmed up and then some, I have never experienced hard starts this way. I really dont think it would start hard even if I didn't wait when its hot. So you may actually be having a VP problem. Maybe.



As soon as it shuts off, the pressure gauge (Dakota Digital) will show the pressure dropping off. It takes 4 readings per second and averages them for the display. It will drop to 0psi within 2 seconds. It usually displays 16-6-then 0psi which means the pressure bleeds off quickly. I agree wait until your lift pump cycles off on key up but you dont need to wait 10 seconds for low pressure. It will occur almost instantly once the pump kicks out. FWIW. How long does your key on cycle last till the pump shuts off?

 

[RobbyRam]

That's with 'their' pump, not mine. Another dealer, believe it or not, wanted $7K+ for a new VP44 including installation!!



Anyway, I purchased the NEW, not rebuilt, VP44 from a wholesaler in Texas, for $750. 00 + core. , including shipping. They're the ones who supply the dealers direct from Bosch, so you know what a killing the dealers are making!



(But this is not anything new to TDR members? Dodge charges $45 for a fuel filter, NOT including installation. Drive down the street to Cummins West and get the same filter for $17. Sigh

Knowledge Is Power)

Bob in Sacto.

 

[WadePatton]

I had a reflash done. It included the "warm hard start" flash. My LP used to crank out 15psi at "key on", now it barely cracks 3psi.



Look for the TSB.

 

[HVAC]

Thank You

I'm glad you remembered me mentioning lift pump pressure during warm starts.



RR, I'm hauling a "02 wreck to Marysville on Monday, are you able to chat early Monday AM or later that day on my way back. Haven't had to opportunity to visit with you for some time. BTW, I'd let you use the pump off this "02 long enough to see if it cures your problem. You save $$$$$$. $$ on a misdiagnosis : ) It's promised to a friend on the east coast, so ...

 

[RobbyRam]

Nowel,

Thanks for the reply so soon. I'm amazed that so many friends are on the TDR this hour!



Ken, of Imler Diesel, was surprised that I was able to purchase a brand new VP44 for more than $200 less than he gets them for at his shop! I told him about the supplier in Texas who is also a supplier for New Car Dealers all over the USA of the same VP44. The only thing different is that they want the old one back, and charge $250 for the core. Still a great price, don't you think , for a NEW pump?



Ken told me that he couldn't squeeze me in 'till September because he's all booked up, five replacement VP44's this week alone, many of which had Edge Comps'(No comment), plus all of the other ordinary work on diesels he had to do. He says he and his whole crew is working 'till ten each night just to keep up.

So, I'll try it myself if necessary.

Bob in Sacto

 

[DAWG-1]

VP44

Robby, Is there a name to this pump person. Thanks,Sam

 

[willyslover]

Robby. . congrats on your find !!. . hope all goes well on the cure [or you find the other issue to be true and have a spare VP]

 

[kboettcher]

NEW PUMP $700..... HMMMMMMMMMMMMM KOOL

 

[Pit Bull]

Originally posted by RobbyRam



He thinks, and, now after several warm starts I agree, that my new 15 psi at idle lift pump is providing too much pressure at start, which has been causing my 'hard to start when warm' problems! What do you think? My truck still runs perfect when driving and in cold start situations.

Robby, sounds like you are learning a lot about your truck (the hard way) I would not blame these problems on the truck and its engineering. The majority of owners drive them for hundreds of thousand miles with no problems. Like they say when you play you pay, no only in $$ but in inconvenience. If you are going to continue to learn on your CTD I would suggest you by another and leave it stock so you will have a truck to drive.

 

[NScott]

Who and Where exactly is this pump supplier inTexas??????????:--)

 

[HVAC]

Supplier In Texas

It's been a while since I checked his site, but do a search for "Cummins Stuff". I think the sites is at www.cumminsstuff.com. I don't see any pricing on the site, so I guess you have to call.

 

[ToolManTimTaylor]

Originally posted by RobbyRam





my new 15 psi at idle lift pump is providing too much pressure at start, which has been causing my 'hard to start when warm' problems! What do you think?

Possible ... Possible inded. My truck with the PE4200 when cranking builds 12 PSI (Defalt even on a stock truck) then ramps 25 when running (Not stock). I don't think its a voltage reduction on the ECM's behaf but that of the bypass within the vp44. My thinking on this is how can a big PE pump and a smaller carter style run the same pressures with the same voltage reduction?.



Am I way off base here?



How is that lift pump wired?



I hope this is the case for you Rob. Wholly hiway robbery 7 thousand frikkin dollars? Gee what was that bad word we can't say here again???

 

[daveshoe]

Originally posted by RobbyRam

That's with 'their' pump, not mine. Another dealer, believe it or not, wanted $7K+ for a new VP44 including installation!!



Anyway, I purchased the NEW, not rebuilt, VP44 from a wholesaler in Texas, for $750. 00 + core. , including shipping. They're the ones who supply the dealers direct from Bosch, so you know what a killing the dealers are making!





DC is the one making most of the killing. When I told a local dealer what some Cummins parts cost , he showed me the Cummins part with a DC sticker over it and said on that particular part, his cost was triple what he would pay at Cummins. He also said that for any warranty repair, the DC supplied computer ''talks'' to DC and shows that parts are supplied BY DC. Otherwise, the repair is not covered by warranty to the dealer.

Now I do not have a lie detector, but my sense is he was telling the truth -- and by dealer, I mean parts counter guy. He stated their markup was . 33 . When you put it on top of DC markup of 200 percent, it really adds up.

My guess is that if all this is true, the dealers would have to have have a second computer and set of books to save us money by ordering parts outside the DC network. Go ahead ,Flame away if you think this is wrong. Just wanted to bring more to the discussion

 

[Pit Bull]

Dave I am sure you are right. Of course I don't care what it costs if DC is paying for it under warranty

 

[nwinters]

TMTT,



Is your PE4200 run off the stock harness direct or are you using a relay triggered from that harness to power your pump?



Nate

 

[RustyJC]

My stock lift pump is making 16+ psig at idle, 15-16 psig cruise, and 13. 5 psig WOT pre-filter pulling our 13,500 lb 5ver. With the stock ECM logic, I have no hot starting problems whatsoever. If you're seeing 16. 5 psig at the time you start cranking, that could indeed be the problem! Depending how long it's been shut down, mine may "spike" for 1-2 seconds anywhere between 2 psig and 10 psig when I turn the key on, but the lift pump will then shut off and the pressure will drop. After going through this cycle, the Cummins fires within 1-2 revolutions hot or cold.



Rusty

 

[Edward]

Re: Re: Just about to replace my VP44, but STOP!! WAIT!!

Originally posted by ToolManTimTaylor

Possible ... Possible inded. My truck with the PE4200 when cranking builds 12 PSI (Defalt even on a stock truck) then ramps 25 when running (Not stock). I don't think its a voltage reduction on the ECM's behaf but that of the bypass within the vp44. My thinking on this is how can a big PE pump and a smaller carter style run the same pressures with the same voltage reduction?.



Am I way off base here?



How is that lift pump wired?



I hope this is the case for you Rob. Wholly hiway robbery 7 thousand frikkin dollars? Gee what was that bad word we can't say here again???

ToolManTim



I haven't actually put a voltage meter on the lift pump harness to verify this but I think the voltage does drop during the cranking cycle. One day I was looking in the fuse panel under the hood and found the lift pump relay and pulled it out to look at it closer. On the side is the electrical symbol for a resister. Finding this and noticing lower fuel pressure while cranking leads me to think that the voltage is probably reduced.



Edward

 

[Steve St.Laurent]

The ECM pulses power to the lift pump - on, off, on, off - during cranking to get the reduced pressures for startup, it does not reduce voltage to the lift pump. They are shooting for less that 7 psi during cranking. When I talked with DC and Cummins engineers when I was putting on the pusher pump setup that I'm running they told me that any greater than 7 psi at startup could cause hard start problems. Also, the stock lift pump does not use a relay - it's driven directly from the ECM. If you are running your lift pump off of a relay the pulsing of the 12v to the lift pump wire is probably too fast to allow the relay to open and close therefore your pusher/relocated lift pump is most likely running at full flow. On my truck I'm seeing 16-18 psi running and a minimum of 14 psi at WOT. This is after 70,000 miles and a little over 2 years. When the pumps were brand new I would see 20 psi running. If I start cranking the truck while the lift pumps are operating then it will take a few seconds for the truck to start. If on the other hand I wait for them to stop and crank the truck then it lights right off.



I've also talked with Mark Chapple (TST) in the past and he has seen trucks with the stock lift pump that had hard start problems because of high fuel pressure. In some of those cases he ended up mounting a shut off switch in the cab of the truck so that you could manually turn off the fuel pump and would have the customer turn the pump off, start the truck, and then turn it back on. I don't know if he tried just letting the pump shut down first or not.