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I've got an ECM that no longer powers the lift pump on an 02 24v Cummins HO. I replaced the VP44 and hotwired the aftermarket lift pump (airdog raptor) to test. Manually supplying power to the lift pump and bleeding injectors did the trick, so now I need to wire it in properly. I read the article on RF noise with aftermarket lift pumps, so I'll modify the harness with a .1 Mfd Orange drop capacitor and modify the pump when I have it out again. Given that my ECM lift pump circuit is DOA, where should I grab a trigger voltage to engage the lift pump relay? I am looking at the light green and black wire carrying ignition power at F18 in the first diagram in the engine wiring diagrams post. Is that the best circuit?

Hi all. This is my first post. I wanted to just post on one of the other vp44 threads but wasn't able too?? Anyway, i have 2002 Ram 2500 5.9 HO 6 speed with 606,000 km's (376,000 miles) probably higher because the truck has always had bigger tires so the speedo is off a little. bought the truck a year ago with 589,000 km's. Truck needed alot of work. I had always heard about the VP 44 and all the problems associated with it so it was actually the Cummins Engine that I didn't want but it was the only one that was available to me at a cheap cost so i bought it. I started doing lots of reading on the VP 44 and try and understand how it all works. I'm a mechanic by trade but I'd really didn't know anything about the VP 44. I read a ton of information that said I needed lots of pressure to keep my injection pump alive but this truck had the last injection pump changed at about 170,000 km so I was skeptical that the injection pump needed to have all this pressure and aftermarket fuel pumps etc when the stock lift pump had been doing the job just fine for many years. The original owner had his first injection pump fail at aprox 90,000 km's. They put a new pump in and once the truck was off warrant it failed again at 170,000. Owner fought with the dealer and they put a new one in under warranty and put the lift pump in the tank. After that he never had a problem ever again. The truck spent most of it's life here in Alberta Canada went all over BC way up to the far end of the Northwest Territories. Hot cold all kinds of towing with a heavy horse trailer all through the Canadian Rockies on regular basis and the truck didn't always have a full tank of fuel he would run it right till empty on a regular basis and then top it up .He did say he used fuel conditioner here and there but definitely not every tank. Fuel filters always came from Dodge or Napa but mostly Napa. I think it probably even ran colored fuel in it from time to time because the truck was used out in the oil field. Also the truck has had an edge juice attitude since about 200,000 km's. It was always run on level 3 (drive) When I first got the truck it had a bit of a hard start issue but that just ended up being bad connection at the batteries. I was really concerned about my fuel pressure because of all talk of needing high pressure. The truck showed 8-9 psi at idle and would drop down to 1-3 psi at full throttle under load. It ran fine and it started fine. I decided from all the reading I had done that this pump didn't need all kinds of crazy pressure to keep it reliable since this truck was basically driven into the ground and rat bagged it's whole life and had (at that time) almost 400,000 km's on the same injection pump. So i ended up buying an Airtex lift pump. Now my fuel pressure is between 13 and 15 psi at Idol, 10-12 cruising and drops to usually no lower than 6 if i'm pulling a hill and i floor it. Drops to 6-8 then usually stays at 8-9 psi till i back out of it. I have no idea how long this injection pump will last and when it does finally fail i know i wont be putting anything other than the stock lift pump back in. I'm not trying to say everyone should do the same just letting guys know that it is possible to get high millage with stock lift pumps. I have read many threads where guys running higher pressure still had lift pumps fail. 440,000 km's (273500) miles and still works great. But my truck is the HO so could that maybe play a roll because arent those pumps different than the non ho's? Also mine is a 6 speed so maybe the Auto trany's get driven harder than this truck did. I know the fuel filter was just filthy when i got the truck. Some dirt was laying down in the bottom of the bowl so original owner wasn't always keeping up on the maintence. I do have an intermittent starting issue though where the truck fires then stalls. Then fires up on second try. Seems like my fuel pressure is bleeding back. I wonder if my inj pump is finally letting go or if it's just a checkvalve somewhere? One other thing is it is quite a bit cooler here than some places in the usa. So that too may have played a roll too on why my injection pump has lasted this long. Great site by the way it will be fun reading all the tech tips. I really like this truck. A bit loud but i'm working on refining it. Can't believe how much power this thing has for having that many miles. Half bush road miles all through the mountains and half hwy miles. One thing i'd like to see is if those larger banjo bolt kits would help my fuel pressure drop on wide open throttle. I can't seem to find any write ups on someone doing a real world test on those things.