I have been involved in electronics as a hobby for over 50 years.I am a Amateur Extra Class Ham Radio Operator. Now that said.I have learned one thing. Heat is the enemy of electronics. No way around it. Especially solid state stuff.I wasn't aware of how much electronics are in the vp44, and I don't know how much are in other injector pumps.Today I drove on a trip that was 35 miles one way, and came back. Ok no big trip. I drove at 52 mph, and tested fuel milage, and fuel pressure to my pump. Milage turned out to be about 25 mpg, and fuel pressure was around 12 psi. for the trip.When I came home I made a routine inspection under the hood, and I reached down and touched the plate where the electronics are located. Wow Hot HOt HOT. Now this is on a 80 degree day with easy driving. I don't even want to think how much HELL the components are going through on a hard pull up a hill on a 105 degree day.It is no wonder there are so many failures of the components..I have no answer to the problem other then maybee putting a vent from an air conditioner on it, and I don't think there would be enough air to do anything.I really feel that the designers never considered this when they put out the product.I am sorry but all the two cycle oil in the world won't cool our components. Lube the pump! Yes. Make it last longer Yes!Anyway that is my rant against the manufacturer today. Other opinions on this matter might help get rid of dissapointment of the makers.:banghead:

Yep and it isn't just a problem with the vp44 either, GM and Ford have had similar issues on different engines with engine mounted ecms and control modules frequently going bad.

Like I got a thread on this... But the simple way to look at this is the fact there is only ONE inlet and 2 OUTLETS for fuel to travel. The INLET is from the lift pump to the injection pump... The 2 OUTLETS... 1. The first outlet is the injectors.2. The second outlet is the overflow valve which only open at 14 PSI of pressure. When the pressure falls below 14 PSI the valve starts to shut till its completely closed by 10 PSI. So now as long as you giving throttle there is fuel flow to the injectors. But if you coast the pump bypasses the injectors and suppose to route it towards the overflow valve. But of the pressure is to low in the pump (internal vane pump wore out) then the overflow valve will not open enough to keep the electronic cool. So like on my truck I maintain a MIN pressure of 15 at WOT and 17 PSI at a idle and I know I'm flowing plenty of fuel through the VP44 during my cool down.

Alright I have an 01 here for a while and he has a fuel temperature thing on his edge monitor that gets its info from the VP sensor (pretty sure). After going to town (10 miles, 55mph) it was 50F outside and the fuel temp was about 80F when I stopped. When I got back outside (20 min later), it was 110F. So we have a 60F jump over ambient. This was surely from the heat soak of the engine block. I am not sure how hot the components can get before they start failing but if the margin on an engine that has been shut off is 60F, then on a 100F day it would be 160F.. Whats more, I went back home and after 1.5-2 hours went by, I went back out and checked it, 110F. So no matter what you do, the engine will heat it right back up. Now remember that this was on a 50F day, where heat transfer to the air would be more than on that 100F day.. So when you turn your engine off on that 100F day, the chip could be over 150F for SEVERAL hours (maybe 5+). The aluminum housing easily collects the engine heat, if only there was a way it could easily shed it. Turning the fuel pump on (if you had a way to make it actually flow) would cool it, but only for the time that it was on. I don't think your batteries are going to be to happy for a several hour use every time you turn it off, or for however long the engine is above the safe temperature limit, as the VP will just keep matching the temp of the block.

Like I had a conversation with ISX one evening about this... Like we all know that everything has a operation range to it... So like for example you take your laptop with you on a hot summer day and place it in the back seat. So now your truck is parked out in the sun baking away. The cab temperatures can rise to 140*F really easy on hot summers day. so even that laptop is baking in that heat. But now try and operate that laptop in that kind of heat at 100% CPU load I'm sure it would die in a short order. But just leave the laptop sitting there in the heat it will survive... But now looking at the VP44 yeah it might operate at 80-100*F of fuel temp while going down the road. But now turned off its getting heat soak sure so is the ECM hanging on the side of the block. But it not like you firing up the engine and going to 100% load from a dead stop. If your lift pump is doing its job and pumping high volume flow by the time you roll out of your yard and get to highway speed the VP44 is sheding a huge amount of heat in the fuel. So I think most of the P1688 failures are cause from low fuel pressure and poor return flow which in turn does a poor job of removing the heat soak on the VP44 electronics. As for the electronics they have been revised several times over the years to improve the performance of the electronics due to heat soak. Like my own VP44 its going just fine as long at the fuel pressure is kept up above 14 PSI I know the fuel is flowing past the electronics and cooling them.

For some reason I remember a couple threads with people who start their truck after a while and it starts and dies and next thing you know they find out the VP is dead. I think the heat gets to them eventually while sitting there and you start it and now it has to run in that heat until it cools. Or it is broke and starting it finishes it off. The heat didn't leave as fast as you might think. So on the first few minutes of driving after the fuel temp is hot, that would probably be the most probable time for failure.

I just dont see anyway we can defeat this problem other then removing the electric components and mounting them in the cab.I don't know if that would even be possible. Well if I had a spare vp44 I would go into it and find out.I don't think it is impossible, there are millions of vehicles with solid state equiptment located at a remote site. I would like to see some pictures of the boards to see how many leads go inside the actual pump.

I just dont see anyway we can defeat this problem other then removing the electric components and mounting them in the cab.

I don't know if that would even be possible. Well if I had a spare vp44 I would go into it and find out.

I don't think it is impossible, there are millions of vehicles with solid state equiptment located at a remote site.

I would like to see some pictures of the boards to see how many leads go inside the actual pump.

Blue Chip has already tried this and failed... There is no way to reomve the electronics from the VP44 and remote mount them... Also something to thing about... When was the last time you heard of a P180 error code being reported on the web??

DTC P0180: FUEL INJECTION PUMP TEMPERATURE OUT OF RANGE

Description

Fuel injection pump temperature is monitored when ignition is on. DTC will be stored if problem exists in fuel injection pump. Possible cause is internal failure of fuel injection pump.

hey guys i have just came up with a spare vp44 and im going to tear it down one day to see what going on in there and i will try to take pictures and everything so every body can see the inside of this monster.

hey guys i have just came up with a spare vp44 and im going to tear it down one day to see what going on in there and i will try to take pictures and everything so every body can see the inside of this monster.

Well theres the man with the plan! Try to get as many of the wiring/sensors as you can. I saw a few tear downs but they never show much on the electronics. Try and show the whole tear down of it showing where the sensors went, everything.

Well now just because someone failed doesn't mean it's not possible.If you don't belive me, ask Christopher Columbus.

hey guys i will try to take as many pictures as i can and ill make sure to put the details in as i go but it will be the begining of the week seems how i gotta work the weekends so as soon as i get to it ill put step by step up on what im doing and ill try not to leave any thing out.

Man there is no heat sink!I cant tell if it plugs or solders to the vp44, but the components are in a oven baking.

So what does the other side look like? The side with the heatsink.. I have never seen it. And how does the chip integrate into it to transfer the heat?

So what does the other side look like? The side with the heatsink.. I have never seen it. And how does the chip integrate into it to transfer the heat?

Just aluminum, with a few little ridges, not much of a heatsink like you would see on a CPU in a computer or something its just a potted circuit board like you see in the pic sitting in a plastic tray, directly over the aluminum that contacts the fuel. Nothing real remarkable as far as cooling capability imo.

I think I have been lied to by the people that sold me my rebuilt vp44.They said the components were solderd to the vp44, and the pictures look like it plugs in to me.I see four connections in the picture so I bet there is a plug out there that would allow someone to make a lead and plug it in the vp44 and the components in the cab then the outside air and air conditioner could cool them down on a hot day, and long pull. Ok so enough two cycle oil, and cooling of components should make them last almost forever!That's my opinion!

I think I have been lied to by the people that sold me my rebuilt vp44. They said the components were solderd to the vp44, and the pictures look like it plugs in to me. I see four connections in the picture so I bet there is a plug out there that would allow someone to make a lead and plug it in the vp44 and the components in the cab then the outside air and air conditioner could cool them down on a hot day, and long pull. Ok so enough two cycle oil, and cooling of components should make them last almost forever! That's my opinion!

No they are sealed in a potted plastic tray and connected to the vp44's inner workings with wires/plugs. You would need to get a machined cap with a groove for an o ring so the fuel wouldn't just pour out, and then run the wires to the cab. This was on an older vp44 i had, don't have one currently to test that with, the one i have right now is under warranty or else I would gladly try to relocate the electronics to the cab.

1 thing you not seeing in those pics is the RPM sensor and fuel temp sensor that is mounted in the hole where the pink rag is stuff... That is not on wires in on a computer ribbon... http://www.turbodieselregister.com/user_gallery/sizeimage.php?&photoid=17236&width=0

Chip thinks he has an answer.Call him.He will tell you.The trick is in the lift pump, as in keeping it running on a timer.He did the remote computer thing and had a problem with rf interference.Maybe he is finished with the r&d.He had a few test trucks going.

Chip thinks he has an answer.Call him.He will tell you.The trick is in the lift pump, as in keeping it running on a timer.He did the remote computer thing and had a problem with rf interference.Maybe he is finished with the r&d.He had a few test trucks going.

He said that 20 min after the thing runs, it hits the max temp. After running around in an 01, it remains at that max temp for hours. I don't know what temperature limit he will set for that thing but if the engine block is not below that temp, it will just heat the VP right back up. He hasn't gave any details as to how it will run or when it will run. All he said was the 20 min thing. Mike also proved that there is no return flow through the VP if the engine is off, chip supposedly has an answer for this though. He needs to hurry up and get more details out there because as it is, I am in more doubt than anything else.