VP44 Injection Pump Problems Solved

VP44 Injection Pump Problems

Before we delve into how to find and solve vp44 injection pump problems, we need to learn a little more about the VP44 pump itself. Sadly every 98-02 Dodge Cummins engine is destined to have a problem with the vp44 sometime in it’s life. Not to worry though! Diesel Addict will arm with the most information possible to make the problem a piece of cake. Lets learn more about VP44 pumps below!

What is a VP44 injection pump?vp44-fuel-pump

The fuel injection pump (VP44) is an electronic rotary distributor pump. The pump performs four basic functions. It first produces the high fuel pressure required for fuel injection. The pump also meters the exact amount of fuel for each injection cycle. As the diesel fuel moves through the VP44 it is distributing the high-pressure, metered fuel to each cylinder at the precise time. The fuel pump then varies the timing relative to your Cummins engine speed.

What caused my VP44 pump to fail? How common are VP44 injection pump problems?

The most common cause of VP44 failure is to lack of fuel. Dodge trucks 98.5 and up are notorious for having weak lift pumps. Unlike most injection pumps the VP44 is fuel cooled and lubricated. Therefore, if its fuel supply comes from a weak lift pump, it is very easy for the VP44 to overheat and cause damage to itself. This lack of fuel results in one of two types of failure within the VP44. One is that the diaphragm inside of the pump is damaged and does not allow the pump to build up the appropriate amount of pressure. The second is that the overheating causes the computer portion of the pump to also overheat and thus, creates a communication failure between the ECM and the Injection pump.

Watch for the signs of a bad VP 44 pump:

What is wrong with my VP44 fuel pump? Trouble code P0216

The most common mechanical failure of the VP44 pump is rupturing of the diaphragm in the front of the injection pump. The diaphragm ruptures allowing the timing piston to vibrate and damage the front cover until fuel bypasses. This will cause the dreaded check engine trouble code P0216. When this occurs your Bosch VP44 Injection Pump must be replaced. The rupturing of the diaphragm is caused by a poorly designed lift pump. When the lift pump does not supply the Injection pump with the correct amount of Fuel Pressure (a minimum of 5psi under load at wide open throttle) the diaphragm then doesn’t have enough positive pressure and ruptures. Dodge has recognized this problem as they will no longer even sell the lift pump that goes on the side of the block; they replace it with a unit that is now mounted in the tank. The average cost of having the lift pump put in the tank is about $800.

What is wrong with my VP44, truck will not start or has white smoke? Dead Pedal

A seized rotor is a common problem with 98-99 trucks or ones with a rebuilt pump without an upgraded rotor, coating, and distributor. This mechanical failure of the VP44 is located in the head of the pump and is a communal problem that has plagued the Cummins engines for a long time. According to Bosch this failure is a poorly “de-burred” rotor. This is a problem in the machining, but has been phased out in later years of production. A seized rotor can be contributed to the lift pump not providing enough fuel to the injection pump. Diesel Fuel is used as a lubricant, so when there is an insufficient amount of fuel the rotor does not get lubricated properly. If you are hitting high RPMs down the road and this is happening, you are not getting the lubrication your pump needs and you are likewise going to run into problems. If the rotor seizes the truck will not start and the VP44 Injection Pump must be replaced.

The last reason for the failure of the VP44 pump is electrical problems with the computer on top of the pump. Heat is the main reason associated with this problem, causing the soldered components to become crystallized over time and make bad connections. Lack of fuel is again part of the problem, because the VP44 is cooled with fuel instead of oil (as the old P7100 12valve pumps). When this problem occurs you will usually experience intermittent hard starts, white smoke and what’s usually referred to as “The Dead Pedal”.

What is the cause of a hard start?

Hard starts, as they relate to VP44 injection pump problems, are caused by lack of fuel or over pressurization by the lift pump.   If a lift pump is going bad and failing to supply the proper amount of fuel to the injection pump, then the truck will hard start due to lack of fuel. However, if a new lift pump has been installed and is pushing over 15 PSI to the VP44 injection you can also get hard starts. The VP 44 is a very sensitive pump and needs approx. 12 PSI to run properly. Once you start getting about 15 PSI to the injection you actually begin to over pressurize the pump and cause it to act as if you had flooded the engine.

The above question “What is wrong with my VP44, truck will not start or has white smoke? Dead Pedal” may help in solving hard starts as well.

What will void my warranty on my VP44 pump?

The VP44 pumps will not be warrantied if a user taps or splices the pump wire and does not use a stealth cover. This is where having a BD Diesel stealth plate comes into play. The Stealth Cover for the 1998.5 to 2002 Dodge 24V fits onto the VP44 injection pump, providing a secure, sealed connection instead of notching the pump wire for power mods. If the wires are cut in any way the pump is no longer under warranty, and any repairs that need to be made to the injection pump will be the buyer’s responsibility.

It is also not advised to run bio-diesel fuel in your fuel tank because it gums up the internals of the pump and rusts the diaphragm. Running bio diesel through your engine will also void the warranty of a pump. VP44 fuel injection pumps are a great pump and work very well only if you give it the right fuel. It is also highly recommend to not be using cheap filters or watered down fuel to improve the quality of life of your VP44.

Where can I buy a VP44 pump?

Having VP44 pump problems? Thoroughbred Diesel offers replacement Bosch Vp44 Fuel Injection Pumps that have been rebuilt by a certified Bosch tech and have been tested on a test stand for 4hrs before the pump is sent to a customer. Bosch VP 44 diesel pumps are also upgraded with all the latest upgrades required by Bosch. The VP44 injection pumps come with a 1yr unlimited mileage warranty. If you unsure or just want some free advice on your pump you can reach them at (866) 737-4966. VP44 injection pump problems are going to happen but we are here to help.

Thoroughbred Diesel also offers several replacement lift pumps, which are better quality than what comes from the factory. If you are placing performance parts on your truck it is highly recommended that you use a performance lift pump such as the Airdog or Fass Fuel Systems. An Airdog or Fass Fuel System will supply the Injection pump with the fuel pressure that it needs no matter what performance upgrades you have on your truck.

Whether you are looking for a stock VP44 pump or a high performance one for those days at the track Thoroughbred Diesel has the pump for you! We also offer VP44 packages that nobody else offers.

shop now at Thoroughbred Diesel

Read about what you need to know about VP44 fuel injection pumps! >>

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  • Jeff says:

    My 1999 dodge deisel won’t start I have 15 psi at the injector pump but that as far as the fuel gets can you help me thanks Jeff

  • tbreddiesel says:

    Yes we could definitely help you out. Call us at 866-737-4966. It would be easier to discuss on the phone then on here. We give out free advice anytime. You can call M-F 8-7 EST Sat 9-2 EST.

  • Asbjorn Ottar Moldver says:

    I am having dead pedal issue problems. I replaced the apps and it seemed to get better. One month later I was doing 60mph on the freeway and went to pass a car, I pushed on the pedal and nothing happened, the truck stayed at 60mph. finally it took off and responded to the pedal. I have never had a problem starting the truck. It starts fine everytime. When the truck is parked on the flat or downhill, I never have a problem. But when I park it on a uphill slant and go to the club for 2 hours and then start the truck and go to take off, it stays in the idle position and barely makes it to the top of the intersection, I make a left onto the flat and it then finally gets fuel and runs fine.
    Bd diesel put their fuel lift pump on and I have been running 28 to 30psi lift pressure for the last 8 years. They had put the Carter lift pump on the same line going to the stock lift pump.. I finally pulled both pumps off and replaced with 150gph fass lift pump, which puts out 16psi.. Do you think the high pressure all these years has messed up the vp44? I have 50hp injectors installed, banks 3.5″monster intake , edge high performance comp box, k@n air filter, bd exhaust brake, 4″ exhaust pipe. bd 400hp auto transmission.
    I get codes 0216, 0230, 1689, 1693 on ecm. Also on pcm codes 0622,1765 and 1693. Please advise on my problem Thank you. Asbjorn Moldver

  • tbreddiesel says:

    If you have a hard start when sitting at a angle, the first thing I suggest you do is go back through your injectors and feed tubes to make sure that you have good alignment. Next, I would suggest to replace the RETURN lines to the vp44, there are three. One at the pump, one at the back of the head, then one at the bottom of the T to the tank. I don’t know if you meant that you were having a hard start when you parked uphill you have a hard start or just a throttle issue. I think your dead pedal issue, assuming you have installed your TPS correctly and your voltages to it and from it are correct, is coming from a faulty VP PSG. Without having the truck here it’s hard to say that for 100% but that’s where I would start in your position.

  • Asbjorn Ottar Moldver says:

    I do not have a hard start. The truck starts just fine every time. The only time I have a dead pedal is on the freeway at times and when I have parked uphill. When I go to leave it stays in the idle mode until I can creep up to the intersection and when I am on the flat, it finally decides to give itself fuel when I push down the accelerator pedal. It then runs fine the rest of the time.

  • tbreddiesel says:

    Really hard to say. Maybe a call in at 1-866-737-4966 would help. That is about all the advice we can give with the information given.

  • Ron says:

    I have a 2002 5.9 Doge 2500 with a VP-44 injection pump. I get an erratic dead pedal. Most of the time this occurs on the interstate cruising at 70 to 80 mph. Sometimes it last for miles sometimes a couple of minutes. The VP-44 that’s on it now is new .I started having this problem about 9 months after I had it installed. I do not get a check engine light or codes. I’ve changed ,crankshaft position sensor, lift pump several times ,fuel filters cleaned the fuel tank, throttle position sensor twice. When it’s running right ,I’ve power to spare and I get 20mph avg. Please someone tell me what’s wrong with my truck ?

  • tbreddiesel says:

    If you have change the TPS and you are still getting the problem, assuming like you said that you are not getting any TPS codes, then I would suspect the VP44. Dead pedal is a common sign of an electronic failure in your VP44.

  • Don R says:

    Well after 7 vp44 pumps in less that 1000 miles. Last one lasted less than 60 miles I think I finally figured out the issue. But the VP 44 is a POS and most of the so called big names selling them won’t warranty them because they daon’t know what the issues are. Yep talked to them all and found the issue with the help of a code reader and much patience. My VP$$ never threw a code I would go out one day and It would not start. Kept blaming dirt and thus no warranty. New tank, new pickup, new fuel lines new injector pump. New bypass filter. Guess most of the rebuilders don’t know how to do anything but replace parts don’t know a problem when they see one.

  • tbreddiesel says:

    You are welcome to call in and talk to us. It seems you are having a lot of trouble and we could see if we could get to the bottom of the problem for you. Toll Free: 1-866-737-4966

  • Greg Gilman says:

    I called you guys today with some questions, thank you very much for taking the time with me!!
    Greg from Ks in SC.

  • tbreddiesel says:

    No problem. Happy to help.

  • Roger says:

    I bought a new v44 pump from thoroughbred diesel and installed it. key way was aligned an truck ran like a bat out of hell all the way home. I start it up it runs fine, I drive down the road with no power till about 1 mile then it acts like I gave it a boost and runs normal until five minutes at 65 miles an hour then I have to mash on the throttle to get it jumping again. do you think the key way isn’t aligned properly. I did a smog test and it said injector timing off. could it be the cam sensor

  • tbreddiesel says:

    What codes are in the truck? What is your lift pump pressure? What was the original failure that led you to replace the VP? This will be a more in depth conversation, if you would feel more comfortable give us a call at 866 737 4966 and we will be glad to help you.

  • Mike Moore says:

    Hi I have a 2001 dodge. 24valve starts and runs normal pulls great but only revs up to 1100 rpm. Do you think it could be a injection vp44 pump failure? Thanks , Mike

  • tbreddiesel says:

    It could be the VP or an ECM failure. What codes are in the truck?

  • Junior says:

    I got the same problem that Mike Moore got I don’t know what to do … Got you find the problem?

  • tbreddiesel says:

    Like we asked Mike. It could be the VP or an ECM failure. What codes are in the truck? You can call us at (866) 737-4966 and we can help figure it out. Quicker than commenting back and forth.

  • Bob says:

    i have a 2001 while driving down the road it shut right down i have good fuel pressure the truck will start but dies after 5 seconds .It will start back up everytime but dies right out i have no codes and i cracked all the injector lines and i have fuel coming from all lines any help would be greatly appreciated

  • mikemcm says:

    I have a 2011 diesel 350 dually that periodically drop to idle while in drive.
    This can occur at any speed and any load.
    The vehicle has 25K miles on it.
    The CEL does not come on.
    I shift to neutral and back to drive,the pedal recovers and power is restored. I don’t stop.Just into neutral and back to drive.
    This is something I cannot reproduce as it can be many miles between occurrence
    Any ideas?

  • tbreddiesel says:

    I would scan the ECM for a soft code and see what you get. Could be a TPS sensor.

  • tbreddiesel says:

    Sound like ECM. Do you have any codes? Have you ran the truck on a breakout box?

  • mikemcm says:

    No codes identified.
    Truck not run daily.Am installing “ultra gauge” for next trip.

  • jo says:

    Sounds like for a preventative measure a better lift pump should be installed and that will keep the VP44 healthy. does that sound about right?

  • mikemcm says:

    ultraguage installed.
    Vehicle failed after 12 hrs into 14hr freeway trip.
    lost power and dash lites.
    Ultaguage did not show any codes,hard or soft.
    Restarted vehicle,all power and lites restored.
    No further problems on trip.

  • G.Wayne Hild says:

    I’ve been experiencing the dead pedal issue for a few years and discovered that pressing the accelerator pedal twice returns control after the second pressing if pressed slowly and not hastily. That also was the least of my problems and the engine refused to start and that was solved by cycling the key thru its cycles several times and then trying again and instant starting.Now very recently the engine will stall and not start and when it does it seems to have been “flooded” and will miss under full throttle till it clears and then everything is okay again and that has become an issue requiring towing. I’ve already convinced myself that another pump is required, The original pump was replaced with a rebuilt one that I believe the internal microprocessor that I have been told is not replaceable by the owner/anybody went bad after the warranty was ended. What should I do? Tell me your best knowledge as the fuel supply is okay, filter okay and pump pushes enough fuel to bleed the air out of the lines and filter after replacing it. OOps sorry the codes are 1682, 0122, 0500, 1693. And the truck is a 2000 Dodge 3500 5.9

  • Tom Kilch says:

    Hi – I have a 99 Ram 3500 and have been having intermittent starting issues. I turn the key, bump the starter and the lift pump does not run. Turn key off, on, bump starter, no lift pump. Do this many times, then finally lift pump starts running, and truck starts and runs perfect all day. Now its to the point that it wont start at all. I’ve “hardwired” the lift pump to run, and gauge is showing plenty of pressure, but it will just crank and not fire. Until the truck commands the lift pump (and I’m assuming the VP44) it will not start. I’ve run many diagnostic procedures to try to track down the problem: 1) Replaced relays for fuel pump and ASD relay with new. 2)Checked voltage going to lift pump on pins 7 & 6 – good power and ground with ignition on and cranking. 3) Hot-wired pump with 12 volts and a ground – truck starts and idles. 4) Continuity check on all wires going from VP44 to the ECM – all checked OK with no shorts to each other. 5) Just sent ECM for rebuild/repair – returned “working” but still wont start. Really at my wits end with this. Any ideas what I might have overlooked?

  • Shawn says:

    OK I’ve got a confusing one. 99 ram 2500 24v 5.9 Cummins. stock all original engine 178k miles. only mods done are a diablo power puck, full exhaust, Fass ddrp lift pump, beans sump, and some gauges. Here’s the problem. runs absolutely perfect, no smoke on start or while running. but will not start on its own to save its life. every now and then i can get it to start after 30 seconds or so of cranking but most times it requires a burst of ether which is why i don’t drive it now. i did a compression test and I’ve got 390 to 450 across the board. i tried unplugging the lift pump and cranking it to see if that helped and nothing. plugged it back in and it fired on the first hit. tried the same thing the next day and wont start at all. I have also resealed the injectors and put new o-rings on them and the crossover tubes, replaced all of the banjo bolt washers and replaced the return check bolt on the injection pump. I am totally stumped at this point.

  • tbreddiesel says:

    You have a leak down somewhere. I would suggest replacing your return lines. That’s always where I start. The return lines are notorious for allowing air intrusion which will cause a hard start condition.

  • Shawn says:

    but wouldn’t having the sump pulling fuel from the bottom of the tank, rather than using the draw straw, remove any reason for the return side to cause any problems?

  • tbreddiesel says:

    The problem is that the lift pump has power while you are cranking in both scenarios. Having positive pressure to the vp44 while cranking, if you have a bad diaphragm, will cause the hard start. Do this, get the truck running, then shut off. Once you go to restart it talk all power away to the lift pump. If the truck starts, shut it off immediately. You can have the ECM updated at that time by Chrysler. The latest flash will not let the lift pump to have any pressure while cranking, then begin running when the engine is running.

  • Shawn says:

    Thank you. I will try this when I get home and report back.

  • Shawn says:

    I just reread thay and I miss understood the first time. I have actually tried this already. when I did it would not fire withe the lift pump unplugged. but then fired right up after I plugged it back in. I tried the same thing the next day and it wouldnt start with the pump plugged in or disconnected

  • tbreddiesel says:

    We still think you have a leak down. With what you have replaced, we still would attack the return lines.

  • Shawn says:

    Sounds like I’m replacing the return lInes then. Thank you for the help.

  • Eddie Daniels says:

    Hey guys, here’s a tricky one. 01 2500, runs, starts and everything else perfectly. UNTIL…. it gets to operating temp and as soon as you let off the throttle a TON of white smoke comes out the tail pipe. I mean enough to where I cant even see the cars behind me. Smells like fuel to me. Besides that the truck runs good. Egts are higher than normal since this started. VP going bad? bad injector? it doesn’t do it under load, only when letting off or at low rpms and only when it gets to operating temp. 150 injectors, bigger turbo, stage IV tranny, edge smarty stack.

  • Curtis Benton says:

    I have a 99 cummins 5.9
    Every onec in a while it feels like it missed a heart beat while driving it does not matter what speed you are going. It has never shut down. If you are on cruise control it will come off cruse control when this happens. Just touch the accelerater pedal and continue going any ideas as to what the cause is.

  • tbreddiesel says:

    Does the truck trip a code when it does this? It sounds like an internal timing problem with the pump.

  • tbreddiesel says:

    Is the truck throwing any codes? This could be a TPS sensor dropping out or even the IAT sensor in the pump.

  • curtis benton says:

    I took it to a auto repair shop to have the fuel filter changed and the diffrential fluid changed .at that time i was told that the lift pump was dead and they could not change the filter because of this. I bought the lift pump and filter and changed it myself. I have driven it about 70 miles so far without a prblem yet .could the lift pump caused the problem i was having.

  • tbreddiesel says:

    @curtis Yes, absolutely.

  • DavidP. says:

    2001 cummins 2500, auto, 4WD, issue is at moderate throttle the engines skips/bucks/misses. Been running 10psi fuel at idle and 4-5 psi WOT for years. Suspected the in the tank FP was the culprit so a FASS system was put on and now running 15psi. Same issue is present. Light throttle, no skip/miss. Moderate throttle, skips and misses. No codes observed. As a diagnostic the APPS and MAP sensors were replaced prior to the FASS install. Engine has 114k miles with original VP44. I’m in Phoenix and it is HOT. Now I suspect the VP44 *ouch*. Please help.

  • DavidP. says:

    As a courtesy to all who may be awaiting a response I have an update to share. I replaced my VP44 as it was the next step to solve my issue. It did not resolve my issue of skipping/missing/bucking! That was truly a disappointment as it cost me $1500. But the good news is I have a new injection pump. Prior to replacing the VP44 I had no codes stored. After the VP44 install I checked for codes and low and behold a P0236 was presents. OMG! The boost sensor had been replaced 8 months earlier and was not considered a culprit. A new boost sensor was purchased from NAPA (lifetime warranty) and installed. Jumping Jehosafat my problem is solved!

    Lesson learned: A bad boost sensor will not always throw a code. It takes 5 minutes to replace and should be the first item to suspect. Having a known good spare sure would be good to keep in the truck

  • Now very recently the engine will stall and not start and when it does it seems to have been “flooded” and will miss under full throttle till it clears and then everything is okay again and that has become an issue requiring towing. I’ve already convinced myself that another pump is required, The original pump was replaced with a rebuilt one that I believe the internal microprocessor that I have been told is not replaceable by the owner/anybody went bad after the warranty was ended.

  • Scott Bursley says:

    I have a 98 and 1/2 dodge 2500 yesterday was driving and it started to like spit and sputter blew a little white smoke then just died and will not start i have uograded the pick up pump in the tank. now im thinking it needs a pump, what might your thoughts be..

  • gerald v says:

    i own a 1999 dodgeram turbo diesel 2500 seris ex cab. ihave changed apps sencer before but it does the samething, start it up from overnight starts fine runs fine but no accelator petal not till it’s operating at normal temp,but i still have to kill the engin and restart,or while it’s either cold or hot i can disconnect the batts. and apps connector then reconnect, do thekey on and petal to floor and back up off with key and crank up and everythings fine again . any ideas whats going on?

  • Donald says:

    Hello there I’ve got a 2002 Dodge Ram 2500 Cummins.
    The problem I’m having is that I start my truck and the idle goes to 2000k rpm with out any hesitation, I hit the throttle and it will respond but the idle doesn’t come down ever.
    I changed my APPS, map sensor, and I replaced the ecm, it doesn’t have any check engine light, just starts up and idle jumps to 2000k rpm. It shuts off with the key and starts right up no issues.
    Possible Vp44 failure?
    Any help is greatly appreciated, thank you.

  • tbreddiesel says:

    Did you replace the ECM or the PCM? Normally, we find that this is an ECM related failure.

  • Phyllis Ball says:

    Have a 2000 Dodge 3500 Cummins starts up with no problem 15psi. after about 5 – 10 mins fuel pressure gauge goes to 30 psi truck starts running rough and acts like it wants to shut off. Shut it off for about 15 mins and it does the same thing all over. Seems like it’s starving for fuel.

  • tbreddiesel says:

    What type of lift pump? Have you verified those pressure with another gauge? When this happens are you noticing anything else like a rise in voltage?

  • Xavier says:

    i have a 1999 2500 Cummins. The truck starts up just fine but is blowing out white smoke and losses power on the highway. I have changed the head gaskets and it still blows white smoke and losses power. Could it be the VP44 injection pump?

  • tbreddiesel says:

    It could very well be the VP, could also be another motor problem. If you have VP codes, I would suggest the VP.

  • peter Morris says:

    I have a 2002 2500. It will not hold idle speed. It starts easy but it jumps from 600 rpm to 1200-1300 RPM. It surges going down the road cannnot hold a steady speed. It does not have a check engine light so no codes. Any suggestions?

  • tbreddiesel says:

    It could have a “soft” code in the ECM that does not trip the SES light. First thing to do is check codes. Then check lift pump pressure. Give us a call and we can walk you through it 866 737 4966

  • will the crank or cam sensor keep my 2000 ram vp44 from starting ?

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