Tractorman

I have tried several engine oil pressure switches, but they don't last. The high frequency pulses from the VP44 destroy them in a relatively short period of time, even with a snubber. The longest lasting one lasted for about a year. I installed the switch in the photo below one year ago this month (10,000 miles ago). So far, I like this one the best. It comes with 3 terminals - common, normally closed, and normally open. It is adjustable (a winner here) and comes preset at about 10 psi. I also like this one so far, mainly because it is still working! I am posting the following information because I think you have not purchased your AirDog Raptor 150Gph lift pump, yet. I think that lift pump volume is way overkill for your application. After years of thorough research I have found at least two groups of people who have installed a flow meter in the return flow line between the VP44 and the fuel tank and test drove their trucks under many different operating conditions. I have done my own fuel return flow testing of the VP44, as well, In fact, I even went one step further and disabled the lift pump and routed a hose around it. The return flow from the VP44 remained unchanged. I drove the truck for 30 miles under all kinds of throttle applications. It drove no different than it did with an operational lift pump. All of our test results have come to the same conclusion - lift pump pressure has no bearing on the volume and pressure of fuel flowing inside the VP44, or how much fuel is returning to the tank from the VP44. We have all learned that it is the VP44 internal fixed displacement vane pump that provides the fuel flow for the operational and cooling needs of the VP44 injection pump. The lift pump does not provide this. However, the lift pump does provide a flow of fuel greater than the volume required by the VP44. As long as there is a positive pressure at the inlet of the VP44, the fuel supply required will have been met, even under the most demanding VP44 operating conditions. How a fluid under pressure and flow behaves is much like how electricity behaves. In electricity you have the following:. * Electromotive force (electrical pressure) measured in volts. * Electron flow (current) measured in amperes * Resistance to electron flow (resistance) measured in ohms So you have pressure, flow, and resistance In fluids you have the following: * Pressure - usually measured in pounds per square inch (psi) * Flow - usually measured in gallons per minute (gpm) or gallons per hour (gph) * Resistance -something restricting the flow of fluid - also usually measured in pounds per square inch (psi) Again, you have pressure, flow, and resistance When working with electricity, we have relatively inexpensive meters to measure voltage, amperes, and ohms (electrical pressure, current, and resistance). We use these meters responsibly to measure the appropriate property of electricity to draw responsible conclusions. Would you modify an electrical system based on one gauge - a voltage gauge - and not consider the current flow or the resistance of electrical loads? Probably not. When working with fluids, the only inexpensive measuring device is a pressure gauge. Flow meters are very expensive and can be difficult to install. So, we usually end up with only a pressure gauge as a tool to diagnose a fluid flow problem. Without a solid understanding of the physics of fluid under pressure, flow, and resistance, diagnosing a fluid flow related problem with only a pressure gauge can be difficult. Misunderstandings of how things operate can easily occur. Now, we get to our VP44 fuel system with a pressure gauge and ONLY a pressure gauge. No flow meter in conjunction with other pressure gauges to evaluate a complex operating fuel system. Nope. Just one pressure gauge location for over 20 years of VP44 operation with many folks making decisions and drawing conclusions based on the reading from that pressure gauge without even considering fuel flow and the resistance to fuel flow. Even worse - not even considering that there is another fixed displacement feed pump in series within the same circuit (the fixed displacement vane pump inside the VP44). This is only my opinion, of course, but I completely disagree with the "it is imperative to monitor fuel pressure and prevent it from dropping below 15 PSI at all times." part of that statement. Similar statements have appeared over the years on this site stating that the VP44 could be harmed by having fuel pressure fall below 14 or 15 psi. This is simply not true. It has also been stated on this site that when fuel pressure falls below 14 psi, there is no fuel from the VP44 returning to the tank, so no VP44 cooling. Again, simply not true. W-T, my original VP44 failed at 64,000 miles and was replaced under warranty at 87,000 miles. The warranty also covered the "fix" at the time, which was to install a relayed in-tank lift pump modification. Before I took the truck in for repairs, I had already heard of the horror stories of faulty lift pumps taking out the VP44. Of course, at the time I believed them - why shouldn't I? So, I strapped a fuel gauge onto the driver side wiper arm and drove the truck back and forth to work for a week (250 miles). The lift pump pressure stayed between 12 psi (idle) and 7 psi (WOT) one hundred per cent of the time. Hmmm. After the repairs the truck drove much better. The very next day I strapped the same fuel gauge onto the wiper arm again and went for a drive. 6 psi at idle and 3 psi at 2000 rpm wide open throttle. Hmmmm..., again. I went back to the dealer and talked directly to the mechanic - a very knowledgeable guy. He said that those low readings are normal but he readily stated the he did not understand why this was the direction Chrysler decided to go. I told him not to worry about it because with my background in fluid power, I figured that as long as there was always a positive pressure at the inlet of the VP44, the VP44 would be happy, so I would be happy. I have currently logged 283,000 miles on this re-manufactured VP44. I used the in-tank lift pump for 160,000 miles (6 psi at idle, 3 psi WOT). According to a lot of information from this site, this VP44 should have been killed in short order. I elected to replace the in-tank lift pump (still working fine) with a used frame-mounted FASS (65 gph, I think) on the frame rail just in case of an in-tank lift pump failure. The used FASS lift pump shows 12 psi at idle and 6 psi at 2000 rpm WOT (with a mild tune on the Smarty S03). That lift pump is still being used and has logged over 120,000 miles. So, in conclusion my re-manufactured VP44 has never seen over 12 psi...., ever. Just for the record, I use no fuel additives nor any two-stroke oil. So...., @Basranabread, if I haven't bored you to death by now, the pressure switch in the photo can easily be adjusted to suit your needs. I adjusted mine to turn off the warning light quickly after the engine has started. I didn't set it at a specific pressure. In one way you can make it behave similar to a gauge. Set the gauge at a fuel pressure that would make the warning light come on under a heavy throttle at a specific rpm of your choice. Then when you drive your truck under those conditions, the light will begin to flicker when the fuel pressure nears your setting. @W-Tand @Mopar1973Man, I mean no disrespect to either of you. Both of you have provided information many times that has helped me resolve problems or, in many cases, has provided me information to make my truck a nicer vehicle to operate. So I thank you both for that. - John

I understand. A question for you, even though it is not related to your starting issues. Does your lift pump normally keep running with the key in the run position and the engine not running? Hopefully, you have the engine started by now. - John

I watched your video. Your "wait to start" light went out at 15 seconds into the video yet you didn't crank the engine until 45 seconds into the video. Why did you wait? Since it sounds like the truck is close to starting, I would just bump the starter and leave the key in the run position. The lift pump will run for approximately 20 seconds. Do this two or three times and then try starting the engine immediately. If the truck is inside a shop or garage and the temperature is above 40 degrees, then don't wait for the grid heaters to cycle - it is just pulling down more battery power. - John

Same here for my '02. Plus I would have to relocate the exhaust brake - didn't want to do that. - John

I think so. I already do that with the original OEM turbo (HX35), RV275 hp injectors, and mild tune with a Smarty S03. My travel trailer is light - a little over 5,000 lbs (GCW is 12,500 lbs) and I pull 6% grades for 5 or 6 miles in 6th gear 60-65 mph (1,800 - 1,900 rpm) with egt's staying right around 1,150°. Kind of similar to what you are asking. I can easily attain 30 psi boost above 1,700 rpm, but a 6% grade will call for about 25-27 psi boost. - John

I think it is because you are on the other side of the world. - John

All of your statements of understanding are true, so I would not worry about harming the pump. One thing you could do if you have any issues at all with the new VP44 is to check continuity of all the wires that connect the ECM to the VP44. Inspect the connectors and make sure that there are no pins pushed back into the connector body. These codes are from you July 18 log entry. Just FYI: P0251 (M) Fuel Inj. Pump Mech. Failure Fuel Valve Feedback Circuit / Problem sensed with fuel circuit internal to fuel injection pump. P0252 - could not find this code in the 2002 FSM P0253 (M) Fuel Injection Pump Fuel Valve Open Circuit / Problem sensed with fuel circuit internal to fuel injection pump. P1688 (M) Internal Fuel Injection Pump Controller / Failure Internal problem within the fuel injection pump. Low power, engine derated, or engine stops. - John

Something doesn't quite make sense here. The cylinders are numbered 1 through 6 with #1 being the front. The firing order is 1,5,3,6,2,4. If you are saying that the the three rear cylinders are not firing, that would be 4,5 and 6 are not firing and the engine us running on 1,2 and 3. Can you clarify? - John You posted the above on November 11. What does "confirmed the hot wire test on the vp44" mean? Does this mean that the engine idled smoothly on all six cylinders? If so, this would mean that there is no mechanical problem and all of the other tests were unnecessary. If the statement means something else, then we need to know what it means. - John

Thank you for the historical log in chronological order. Just one question. The July 18th entry does not say anything about the VP44 that was currently in the truck at that time. How many miles / years? original VP44? or do you not know any information about the VP44. How many miles / years have you owned the truck? Is the "theory" referring to "THE diesel shop to go to" or are they referring the the re-builders of your previous VP44 pumps? - John

I tried it once, but to me, oak just doesn't taste that good. - John

My wife and I were selling our home in the Willamette Valley on the west side of the Cascade Mountains in 2019. I had a 12' x 24' wood shed full of split well seasoned oak firewood (seasoned well over 2 years). By then, we had purchased a 5 acre parcel of land near Baker City in eastern Oregon. I used my dump trailer to haul firewood from the Willamette Valley home to the eastern Oregon property when we traveled there to work on the property. Ended up hauling over six cords of firewood. In February of 2021, the Willamette Valley had a very destructive ice storm. It especially hit hard where I used to live. My neighbor there had two mature oak trees that went down. The following spring I took my 14,000 GVW equipment trailer and tractor there to help clean up my old neighbor's yard. Each of the three loads I brought backnetted over 10,000 lbs. - so well over six cords of firewood, again. We moved into our newly constructed house near Baker City in October of 2020. It is a 2200 sq ft home that is heated solely with the wood stove - propane furnace backup. We are in the middle of our third winter now and I have lots of oak firewood left. I just finished insulating the 30' x 36' shop that I am building and I am now heating the shop with a wood stove, as well. I am really going to miss burning the oak when it finally runs out. The firewood source around Baker City is red fir and tamarack - good firewood, just not the same as oak. - John

I agree. I currently have 370,000 miles on the OEM head gasket with running a mild tune for the last 100,000 miles. No studs. The truck has done its share of heavy hauling (up to 21,000 lbs gross combined weight) over long distances throughout its life. - John

If I were in your shoes, I would investigate the cause of the above-mentioned turbo performance issue before I started making any modifications to the engine. You could have something simple such as a broken clamp on a hose connection on either end of the intercooler or at the intake plenum. The leaking connection will only be heard under boost and the sound produced can vary widely. And, of course, black smoke would come out of the tail pipe due to not having enough air for the amount of fuel injected. If the turbocharger is found to be at fault (determined after a close inspection), then I would want to know what caused the failure and why before moving forward. - John

Dennis, welcome to the forum. Turbos are usually pretty bullet proof. Could you elaborate a bit more on "the turbo started acting up"? - John

Maybe you could put together the historical log mentioned earlier? - John

My truck is also an '02. The original VP44 set the P0216 code at 64,000 miles. Drove it that way for another year (learned how to get around the limp mode). VP44 replacement and lift pump relocation to tank was performed under warranty at 87,000 miles. The re-manufactured VP44 installed then has now logged 283,000 miles - no 2-stroke oil and maximum lift pump pressure ever observed is 12 psi, and that's at idle. The re-located in-tank lift pump ran for over 150,000 miles (over 11 years) at 6 psi idle and 3 psi wide open throttle. I changed location of the in-tank lift pump to a frame mount lift for easier access in case of failure. The in-tank lift pump never failed. I think there is a wide range of quality control with re-builders. The professional VP44 re-builders not only use new PSG' and fully test the pumps, but also use updated internal parts. - John

@Timburrr, since your particular problem has been hard to diagnose and it has occurred over a long period of time with many actions taken, can you make a log showing the history of your truck before and after the problem occurred. The log would show events that happened, things you observed, repairs you made, checks that you performed, etc. The log would like like the example below: Date Odometer Description 5-5-21 259,820 Installed new VP44 injection pump with new PSG by (vendor name) 6-9-21 260.020 Truck died on way to work. Would not restart, required a tow to dealer 6-25-21 260.020 Dealer called and said the PSG on the VP44 failed I think a log would help everybody see a clear picture of the events as they happened. And, the log could be copied to the latest post so that it would be fresh information for any forum member to respond to. Even if the dates and mileage were approximate, it would still help greatly. - John

Saying that you are "on your own" was a poor choice of words on my part. I apologize for that. However, the forum will need information regarding how the your headlight relays and bulbs are wired since your current headlight wiring is not likely to match the FSM wiring diagram. Also, if you let the forum know your skill set, then the forum can ask the right questions and help get this figured out. It is possible, although not likely, that both low beam filaments are burnt out. You don't want to skip this step. While you are checking, identify the bulbs - that will help with troubleshooting. - John

Since it has been modified, you are on your own here. I would verify whether the relays are using positive or negative switching (both on the coil part of the relay as well as the switch part of the relay). Then troubleshoot the lighting circuit from there. - John

Is it a factory 4 bulb system (Sport Package) or a modified 4 bulb system (after market)? - John

I agree. There are other areas for electric vehicles that are not being talked about much - small off road equipment, such as a mini-excavator. One of the most undesirable aspects of an electric vehicle is the large amount fixed weight (the batteries) the vehicle must carry around all of the time. In a mini-excavator, the weight of lots of battery power would be an asset. The heavy weight of these batteries would be part of the needed counterweight. There are already a few manufacturers of EV excavators. I have a Takeuchi TB016 mini-excavator. It weighs about 3500 lbs. It is powered by a 3 cylinder 14 hp Yanmar diesel engine. It would be an excellent candidate to be powered by a large battery pack. The high starting torque of DC electric motors would easily propel the tracks - no hydraulics. The volume of oil needed for the electric powered on-demand hydraulic pumps used for the auxiliary hydraulic circuits would be significantly reduced. A lot of pluses. - John

All of the air that leaves the blower chamber immediately flows through the evaporator core. If the evaporator core is partially blocked, then you will have reduced air flow from the vents - not reduced air temperature. In fact, the air temperature from the vents would probably slightly higher because of the longer saturation time while flowing through the heater core. You have not mentioned anything about low air flow - you have only mentioned low air temperature. It is possible the thermostat could be a problem, but I don't think so. I run a 180° thermostat in my truck and my heater works fine. I think that you are down to a partially plugged heater core, or the blend door actuator is not indexed correctly, or the blend door itself is damaged / not sealing. I think it would be worth a try to remove the blend door actuator again and rig something to prop the blend door in the correct position to ensure that all air is flowing through the heater core. If nothing changes, then you can rule out a blend door actuator problem. I know you will get it figured out. - John

To make the rear screw installation easier, I used a longer screw with a spacer (can't remember the length). This made the head of the screw more accessible for starting the threads and for keeping the tool driver on the screw. I don't think I would worry about the actual temperature coming from the vents. You will know if it is fixed. - John

Thanks for sharing your experience. Your story has well demonstrated how quickly things can get out of hand. Many times a safety device, such as a clutch safety switch, is mandated, but the reason is not thoroughly explained, even though the reason may seem obvious. Then, as time goes by, the value of that safety device changes even though the device itself hasn't changed. Let me explain (using the clutch safety switch as an example). In 1984, I purchased a new Ford E150 van with a 4 speed manual transmission. It had a clutch safety switch. I never modified it. But, if I would have modified it and activated the starter in gear while outside of the vehicle, the following could happen, even with the park brake set. * The engine could start before I let go of the key. That would be the worst case scenario, but probably would not happen. Why? Because back then most engines were gasoline engines and the engines were carbureted. Those engines would usually take a few revolutions of cranking before the engine would start. Plenty of time to let go of the key. Also, the resistance of cranking the engine in gear with park brake resistance would greatly reduce the chance of the engine starting. But the event would probably scare the heck out of me. So, fast forward a few years and you will find that the safety device has not changed, but the instant starting of a high torque, low RPM diesel engine has. Therefore, the risk of serious property damage or serious injury has greatly increased. @JAG1has illustrated this well. @JAG1has also made a good point regarding a tire shop employee starting the engine in his truck using poor safety habits - a risk that I did not think of. In this case the employee is relying on the operation of the safety switch and he is not placing himself in the driver seat every time he starts an engine. Over 50 years ago (before the addition of clutch safety switches), safety awareness regarding starting manual transmission engines was greater. Now, the safety awareness is posted within pages and pages of other safety awareness items. Not likely to be read. For all of these reasons, I think I will keep the clutch safety switches in my truck and my tractor fully operational. - John

According to the wiring diagram, it should work without any side affects. If you decide to do it, just be sure you continue to practice your learned engine starting safety habits - no starting the engine without being fully seated in the driver seat. - John