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How to remove the Bosch VP44 Injection Pump the quick and easy way. Takes approximately 45 minutes for me to remove the VP44 Injection pump. Remove the Mopar1973Man Crankcase vent (if applicable) Using a 10mm socket remove the four air horn bolts and one dipstick bolt. Using a 7/16 or 11mm socket loosen the top clamp of the intake boot. Move the grid heater and intake horn out of your way. Pack a shop rag in the intake to prevent stuff from falling in the intake manifold. Using a 13mm socket loosen the 3 bolts holding the APPS sensor and unplug and move over toward the driver side fender. Now unplug the VP44 main connector and wire tap . This connector is a two step plug lock. Pull the release tab and wiggle the plug out then pull a bit more on the release and the plug should release fully. Now using a 10mm loosen the 3 bolts holding the 1,2,4 injection rail in place. Using a 3/4" wrench loosen 1,2,4 injection lines. Now remove 1,2,4 injection lines as a group. Using a 3/4" wrench remove the overflow valve banjo and remove your supply line (may differ from mine being a big line kit) Now remove the crankcase vent. Just unscrews normal right hand threads. Do not pry on the nipple. Use an oil filter wrench or a strap wrench to loosen stubborn vent covers. Now remove the pump shaft nut with a 1 1/16 inch socket. Be careful removing the nut and lock washer that you don't drop them down into the gear case. A stubby Phillips screwdriver and a magnet is handy you can slide it off the shaft onto the Phillips screwdriver. Using a 23mm socket roll the alternator towards the coolant bottle to bring the keyway on the pump gear to TDC position and then install your gear puller and pull the gear loose on the shaft. Now loosen the 3,5,6 lines but you do not have to remove the injection line set. Now you want to loosen the 2 bolts on the rear bracket with a 13mm socket. Now remove the 4 nuts holding the pump to the gear case. Now careful kick the 3,5,6 lines out there nipples towards the block. Now lightly pry the VP44 injection pump away from the case and remove. Check for the key in the shaft make sure its present. This is what you should have after removal... View full Cummins article

Fuel Pressure Specification For Bosch VP44 Injection Pumps Here is a copy of the fuel system specifications from the Dodge Factory Service Manual. This is for your Dodge Cummins Turbo diesel truck with a Bosch VP44 injection pump. Fuel pressure Normal fuel pressure should float about 14-15 PSI running down the pavement. It should never fall below 10 PSI at all. Here is a colorize fuel pressure gauge to give you a clue of the fuel pressure span you want. You want the needle to stay in the green at all times. Yellow zone is a warning that you should check the fuel filter, lift pump performance, overflow valve, etc. This is undocumented maximum pressure is 20 PSI. Now take notice to the overflow valve is set for 14 PSI so excessive pumping of fuel does nothing for performance except create more heat in the fuel, which in turns reduces the cooling ability of the fuel and adds more stress to the lift pump. So a little extra fuel pressure is a good thing because it ensures the Bosch VP44 injection pump stays cooled and lubricated properly. However, excessive fuel pressure will heat the fuel and reduced the cooling ability of the fuel. Now always remember that the only lubrication the Bosch VP44 injection pump will see is the fuel itself so if you don't have enough fuel pressure it will cause damage to the Bosch VP44 injection pump. It's like the same as running the engine with low oil pressure it will continue to run, but the damage to the engine will occur. On the other hand, the Bosch VP44 injection pumps, which happen to be about $1,200 to replace. Pressure Drop The amount of fuel pressure drop between idle and wide-open throttle. 2-3 PSI drop from idle to WOT is normal. However, 5 PSI or more pressure drop from idle to WOT is pointing out a failed lift pump, plugged filter, and/or plumbing restrictions. 2-3 PSI Is Normal Dropping more than 5 PSI is pointing towards a failed lift pump, plugged filter, or restrictive plumbing. Just to show you the difference in the stock plumbing which is 6mm ID plumbing and most performance pumps come with 1/2" ID plumbing. These pictures will give you an idea... The first picture is a Big Line fitting over the top of the stock plumbing. Then the second picture compares the stock 6mm ID steel lines to a 1/2" ID Big Line hose. The best way to show this example of restrictions is to let's say your house is on fire. You know your garden hose has 80 PSI of pressure, but the garden hose is only 5/8" ID hose. Your wife calls 911 and gets the fire department coming in the meantime you keep fighting the fire with your little 5/8" garden hose and losing the battle. The fire department shows up and pulls a 2 1/2" hose off the truck and charges it at 80 PSI and now winning the battle. Your fire is put out! What is so different? No matter what the size of the fuel line will dictate how much volume can be pushed through the fuel line. Like the story above the water pressure was the same at 80 PSI, but the hose size jumped from 5/8" to 2 1/2" ID hose and the volume changes are the size of hose. So the same thing applies to the stock fuel system. The stock banjo bolts and 6mm ID pipes are just too restrictive and cannot supply enough volume of fuel for that Bosch VP44 injection pump demands. This why I highly suggest you go up to 1/2" ID plumbing. Reasons Why Fuel Pressure Is Critical Let's take a look at a Bosch VP44 injection pump. I've labeled the fuel lines supplying fuel and return line plus the overflow valve. Now I know there is a ton of rumors on the internet of all kinds of minimum pressures for a Bosch VP44 injection pump. I'm going to say stick with the Dodge Factory Service Manual Specifications for fuel pressure. Now let's talk a bit more about the flow of the fuel. The lift pump supplies pressurized fuel to the Bosch VP44 injection pump the overflow valve regulates how much fuel pressure is held. Excessive fuel pressure is returned to the fuel tank. The picture below is of the bleed hole in the overflow valve this image was magnified x10 to show you how small the bleed hole really is. Give you an idea the size of the hole use a single strand of 14 AWG copper wire, and it will NOT fit the hole. The bleed hole is there solely for bleeding air out of the system which air will pass through this tiny hole rather easy but fuel will not. However, if you're looking for long life from a Bosch VP44 injection pump, I would personally suggest you adjust your minimum pressure to 14 PSI this will ensure the overflow valve remain open and a constant fuel flow through the Bosch VP44 injection pump and keep it cool all the time. Let me play out a simple scenario. Let's say my fuel pressure is roughly 10-11 PSI. I'm going to drive up into the back country approximately 40 miles with my Dodge Cummins towing an 8x8 utility trailer. Now the whole trip heading uphill into the mountain towing an empty trailer is going to be enough fuel flowing to the injectors to keep the Bosch VP44 injection pump happy. However, I've spent the day and loaded up with firewood and now coming back down the mountain loaded. I'm using my exhaust brake and coasting most of the way down taking it slow and easy. At this point, the injectors are no longer firing so the Bosch VP44 injection pump is not pumping fuel out to the injectors. Furthermore, the overflow valve closes at about 10-11 PSI so let's say it did close. Now where is the fuel going??? Nowhere! It is pooled up in the injection pump and gaining heat and being broke down. You've also removed the cooling and lubricating of the Bosch VP44 injection pump so now it actually taking on damage. To give you a feel for the fuel flow coming from the injection pump with an AirDog 150 at 17.5 PSI of fuel pressure, I've got a video to explain that quickly. I've heard rumors of some people trying to develop a cool down system for the Bosch VP44 Injection pump but after making the video above, there is just no way to cool down the injection pump using the lift pump of even the AirDog/FASS series. The whole problem is the restrictions inside the Bosch VP44 injection pump and the overflow valve as seen in the video above. So the only way to keep the Bosch VP44 injection pump cool is to keep fuel flowing through it at all times. So to keep the overflow valve open I suggest the 14 PSI minimum pressure. I'm currently at 136K miles on my Bosch VP44 injection pump and still going strong using a 16 PSI minimum pressure and an 18 PSI idle pressure. Here is a short video of stable fuel pressure from 55 MPH to 70 MPH at WOT. Here is another video done with idling, cruising, and WOT operation. Yes. I got a bit carried away and sloshed the fuel in the tank and sucked an air bubble and the pressure fell off. Cranking Pressure Test Here is a simple test on how to do the test for cranking fuel pressure. Pull the fuel pump relay in the PDC and then attempt to start the engine. Pay attention to the fuel pressure gauge during cranking. Be aware this test will trip a P1689 code and light the CHECK ENGINE light. Excessive cranking pressure can lead to difficult starting problems. Suggested Lift Pump Replacement You should replace the stock fuel system completely since it cannot supply enough fuel for even stock requirements without causing damage to the Bosch VP44 injection pump or adding stress to the lift pump. The pumps I suggest are proven and come with a lifetime warranty. These pumps come with a full kit and replace everything from the fuel tank to Bosch VP44 injection pump. AirDog 100, 150, or 165 Raptor 100 or 150 FASS 100 or 150 FASS DDRP (DDRP Ver.2 - 89 GPH) I don't suggest these pumps... Because they don't address the pump location, plumbing restrictions, or come with much of warranty. Stock Carter or Carter Campaign Pump (4090046) Holley Blue or Holley Black FASS DDRP (DDRP Ver.1 - 40 GPH) AirTex Mopar's Notes: That was true for the DDRP Ver.1 However, DDRP-02 is rated at 89 GPH and will hold pressure. It is listed as a Stock replacement pump designed to perform better than the Stock pump, but not for Chips that add fueling. I place a Power Puck on my truck with the DDRP-02 and saw no difference in FP at either idle or WOT, (PP is a timing chip doesn't change the amount of fuel). That said the PP is currently removed from my truck as I overpowered my clutch both loaded and unloaded, back to the stock clutch is fine. Looking for a Valair possible DD organic, or SD Kevlar/Ceramic. It is currently in the stock location and giving 15 psi at idle and 10 at WOT. Information Provided By: rhagfo http://www.cumminsforum.com/forum/98-5-02-powertrain/404412-fass-ddrp-02-a.html#post4197714 Additional Information (About Performance Crowds & Fuel Pressure) I've seen several times where people will link back to performance pump builders and quoting where they say, "(Un-named) proved that 5 PSI, under load, made all the horsepower the VP44 pump could make, even with stock fuel lines, fittings and supply pump." This might be true but there is nothing ever said about the life span of the pump at these conditions. So... Please do not follow these performance crowds into destroying a perfectly good Bosch VP44 injection pump. The fact still remains from Bosch the actual designer of the Bosch VP44 injection pump states that injection pump should return 70% of the fuel back to the fuel tank for cooling and lubrication purpose of the VP44. Being the only way a Bosch VP44 injection pump can do this is to have fuel pressure above 14 PSI to open the overflow valve. Then if the stock Bosch VP44 injection pump with an enhancement box say an Edge Comp on 5x5 can consume 15-20 GPH that means the stock 35 GPH pump cannot keep up with Bosch's design of 70% return volume. So this why products like AirDog, Raptor and FASS was created because they actually meet the demands of the Bosch VP44 injection pump. Then another fact that Bosch will let you know of is that diaphragm damage occurs from operating the Bosch VP44 injection pump at low fuel pressures. Making matters worse is that no Bosch injection re-builder will void warranty a VP44 injection pump with diaphragm damage. Dead give away that you had a bad lift pump or low fuel pressure problems. Please view the Bosch VP44 exploded view page to see there is no diaphragm in the Revision 027 Bosch VP44 Injection Pump Then the other fact is right from the Dodge Factory Service Manual has the minimum fuel pressures (picture at the top of the page). It even states the pressure that the overflow valve requires to open. Refer to the Overflow Valve Testing from the Dodge Factory Service Manual and see that the overflow valve should remain closed at 10 PSI and open by 14 PSI. So if the overflow valve is close by 10 PSI, then you extra cooling and lubrication just disappeared. So ultimately it suggested having a fuel system of no less than 100 GPH supply that can maintain a minimum pressure of 14-15 PSI at WOT. This will great extend the life of the VP44 because it keeps the electronics cooler longer and keeps the rotating parts lubricated properly. So please people let the facts and information from the actual designers of the injection pump (Bosch) and engine (Cummins) provide you proper information for your fuel system for your engine. Don't be swayed by performance shops claim of high horse output with little fuel pressure. As I proved right here doesn't work for the longevity of the VP44 injection pump... Another thing to bring up there are people that are increasing fuel pressures above 20 PSI. Please don't do this. The return port leaving the VP44 pump isn't very big at all. The return port is on the left and supply is on the right. As you can see increasing fuel pressures above 20 PSI put you at risk for shaft seal failure. Increasing the pressure above 20 PSI isn't going to improve the return flow. I say stick with the 14-20 PSI pressure range for seal safety. Additional Information (About Maximum Flow Rates) Here are some calculated flow abilities of the stock fuel system vs. 1/2" big line kits. This is not calculating bend, turns, offices just straight flow for open end plumbing and this is a rough calculation. Pipe Size Gallon Per Hour Flow Rate Gallon Per Minute Flow Rate 6mm ID pipe 75 GPH @ 15 PSI 1.2 GPM @ 15 PSI 1/2" ID pipe 570 GPH @ 15 PSI 9.5 GPM @ 15 PSI Use The banjo bolt Shrader valve to test for fuel pressure, Item 3 in the above diagram. If you have a 98-99 truck the port might be on top of the fuel filter housing. You can see the 90* bend fitting coming out of the top of the fuel filter housing in the below picture. Install a Shrader valve and test from there. I'm hearing of tales of shops, mechanics, or dealers doing the old hook up the fuel pressure gauge and only checking fuel pressure at idle. This is wrong. Because I've seen lots of cases where fuel line restriction, fuel filter plugging, gelling fuel and other thing causing fuel pressure to drop out under load. Like this video from a friend of mine, you'll see he's got awesome fuel pressure at an idle (where most shops gave him the green light). However, what the shops did not test for is WOT at highway speed, and you'll see in the video, he can pull way down to 0 PSI. Anything under 14 PSI is a concern... Anything under 10 PSI is a serious problem. As for having a gauge in the cab all Dodge Cummins trucks should have a fuel pressure gauge in the cab. Because like you seen bench testing with an idle pressure is meaningless if you can't see the WOT pressure at highway speed. View full Cummins article

So the other day my truck would not start. When I turned on the key, the WTS light did not come on, then it would crank and crank and not fire. I opened three injector lines, but no fuel was coming out of them as I cranked. I finally used some starting fluid to get it running. Two of the lines still did not have any fuel coming out of them and the truck was running rough. I closed all the lines, reved the engine up and it finally started firing on all six. I was able to drive it, even shut it off and restart it, but then a few days later when I tried to start it it would just crank with not fire. I checked the voltage going into the VP44 and I do have voltage in what I think is the correct pin. I am not getting any error codes, but am wondering if it might be the injection pump that is bad and not the electronics? the reason for this is the fact that when I opened the fuel lines, even when running two of the lines did not have fuel squirting out of them. Any thoughts of other things to check on before I replace the injection pump. Also, I have taken out the auto trans and replaced it with a 5 speed, do I still need to use the S.O. injection pump? I am not sure if I will gain anything as I do have 75 hp injectors, so it may be just as simple to stay with what I have?

Where can I order a pump at a reasonable cost 2001 V44:ahh:

What's the difference between a truck vp and a midrange vp? can we use the midrange pump on our trucks??:confused:

Was looking through Fuel pump options and came across this place. industrialinjection.com They rebuild fuel injection pumps for diesel engines and tout their abilities, as do all companies, however, may be something to it... http://www.industrialinjection.com/shop/category/pumps/dodge-injection-pumps/ Curious if anyone knows of these guys or not, interested about experiences.

99,6XX miles and the injection pump is failing, again. I ordered the new vp today. I need a fuel pressure gauge because the air dog light must not be completely functional. Am looking at a juice attitude cts, thoughts? Why not get the power as well as monitoring is my thoughts. Occasionally I run red, good or bad idea? Do I need a fuel additive? What would you guys do to my truck to help with A) fuel problems and B) mileage? Can't keep dropping $1000 every couple years on a vp. Air dog has stock 15lb spring, should I change to 17lb? Keep in mind I do have emissions here in Denver.

Does anyone know wher you can find a list of bosch certified vp44 rebuilders? just curiosity.

Made a quick trip to the store and on the way back while slowing to make a right hander the Cummins Died . I coasted to the curb. Could'nt see anything wrong. drain a little fuel for Airdog 150 at water filter too see whats up there, looked ok. WALKED a block and a half to get tools, (I Know:lmao:). Remove Fuel PSI sender and add another gauge and was reading 17 before cranking, just the bump of the started so there is psi to injector pump. Then I called Tow Truck:banghead:. Too heavy for me to push that far. After I got home started reading about this, Ck code and found nothing. Now I ask should i ck the keyway at pump or what next? Any advise would be very helpful.--- Update to the previous post...Let me add that the truck sat around for about a month or so, then when i started to drive it again, I would have to crank it a lot longer to get it started. Before i would really just bump the started a little and it would start right up. And I do run 2 stroke at 200:1.Just thinking again, what about the dowel pin falling out. would it leave a code of something or not?

VP-44 Key Picture On my wifes truck I wanted to verifiy the key was... 1. In 2. The arrow pointed the right way 3. That the number matched the number on the pump I was able to use a 4MP Cannon camera on the closeup setting to capture this picture so we didnt have to use a mirror or scope. If you didn't know... the arrow points towards the pump. the number on the key matches the number stamped on the pump. You can't use another number key

I just had the VP44 and the lift pump on my 98.5 Dodge replaced. At idle, the engine surges from 600 to 800 rpm and wants to die when the accelerator is pressed. The injectors have been bled once, the pump has been primed with the key trick once or twice and I am not sure if the APPS reset has been done. A friend is doing the actual work, he is a heavy equipment diesel mechanic and has never worked on a Dodge. I do trust his work mechanically. Am I right in thinking we need to reset the APPS, prime it a half dozen times and bleed it one more time?It's kind of funny, I have been reading on here for several years now and never had a reason to post. My old 92 12V just never broke down and I'm not smart enough to give a competent answer about these 24V's. I've been in deep do... every since my wife decided I needed a better truck and bought this piece of junk without talking to me. I would appreciate any suggestions you have. I do believe we're on the right track.:pray:There are no codes showing now that the pump has been replaced.Russ is probably the only one who remembers Tudor the Turtle.

New Blue Chip X, Marine Injectors and a valve adjustment, with a new filter thrown in for good measure:cool:

Ok here's the scoop, About a couple weeks ago my 98' 24 valve started stumbling and cutting out, now today she just up and died. It was as if I reached down and turned the key off. Brought it to a garage and he pulled up the following codes: P1688, P0237, P1693, & P1388. I have no clue what's goin on with it, getting married in 18 days and didn't need this :ahhh:Any ideas??Lucky

First of all, Thanks to Michael for taking the time today to help me out, I just started working on troubleshooting the harness to see if its the problem

Can the main computer shut down the Bosch VP44 if there is a cooling problem or temp sensor error? I have been having cooling problems on hot days and under load. After flushing radiator, the engine ran normally for 5 minutes down the freeway and then suddenly stopped and wouldn't start. (as if it ran out of fuel) . Fuel pressure from lift pump is OK. Fuel to the injection pump inlet OK but nothing at the injectors. There was no missing, no smoke, no roughness, good 23 mpg, just before shutdown. Coolant temp was normal. It seems odd that the VP44 would fail after I was working on the coolant system. Is there an internal fuel shutoff solenoid inside the VP44? Any insight would be appreciated!

You are never going to believe it, the vp44 CAN be "rebuilt" in your shop/garage/lean-to!! Since my pump went out I have been feverishly searching for a cheap fix or the at least the cheapest rebuild I could possibly find……how does about $40.00 sound?!?! I have researched this in depth and found the common problems that cause vp44 failure, most of them are manufacturing process related (burrs left on metal components, pump case wearing through due to lack of lubrication, and parts seizing due to improper lubrication) Once the components have worn down they seize and of course the pump stops working, the less common failure is the electrical pack solders become weak and loose their proper connection, the connections could possibly be re-soldered but for the most part, when the electronics fail the pump has to be sent in as the electrical pack is calibrated to connect to the ECM on a calibration bench and unless you have a 100k to drop on a bench you may as well get a reman pump. As for the rest of the internal moving parts, it seemed to me you could just replace them….better yet, I found a guy that simply honed the parts and sanded them down with some fine grit sanding paper to relieve the clearance on these parts, he replaced the gaskets and lo and behold….his truck is now running!! I am in the process of ordering the gasket set he found and also am looking for the proper tool to remove the tamperproof bolts that hold the pump together, within the next couple weeks I will be attempting to rebuild my pump assuming the internal parts are seized and the electronics pack is not toast, once I have it apart it should be relatively obvious what the culprit is….. Here is a link to the site I found this information on, http://www.dieseltruckresource.com/dev/vp44-rebuilding-t111329.html in this thread you will find the part number as well as the contact information for ordering the gasket set to fix what is a ridiculously expensive problem for an otherwise excellent truck. This already worked out for at least one guy that had a bit of common sense and know how, I see no reason the same line of thought wouldn’t take care of many peoples vp44 headaches!! GAWD I HOPE THIS WORKS!!!!!!!

See attached file. I'm trying to figure out the path of the fuel flow within the VP44 injection pump (IP). I'm interested in the slight possibility of additional cooling for the IP. Does anyone have any other pics or drawings or diagrams they can upload? I've done a bit of research on forums and I've talked to BlueChip at lengths. The VP44's computer sits on top of a heatsink or is integral to it, this is bolted to the IP housing, and the diesel fuel passing under the heatsink cools the computer. There is a vane pump at the inlet of the VP44. The "ww.chinahanji.com" drawing is helpful. I'm thinking the area directly beneath the computer, adjacent to the inlet and outlet ports is a cavity and inlet to the vane pump. The fuel enters the cavity thru the inlet port, the cavity is pressurized to 14 psi via overflow valve (or pressure release/check valve, whatever you want to call it) that is integral to outlet banjo bolt. A portion of the fuel is taken from the cavity by the vane pump and fed to the high pressure rotary section of the IP, the rest is returned to the tank thru the overflow valve. This flow of fuel, most of which is returned to the tank is what cools the computer. Does anyone know what the bottom the computer/heatsink looks like?- is it finned or flat? The smaller cavity that the heatsink/computer also covers is shown with what looks like a wire ribbon passing thru and has a seperate gasket. Does anyone know if this is also filled with fuel? Please, are there any VP44 guru's out there that can correct me? VP44 pics1.doc