Engine/Transmission (1998.5 - 2002) VP44? codes 1688, 1689, 251, 252

[bigredblur]

Well, it finally happened to me I believe. I was driving down the road in McKinney and the dash lights came on. I immediately put it in neutral and tried to restart but it wouldn't. I coasted into a supermarket parking lot and MAN was that a hard steer with no power. I finally stopped and tried to restart the truck. It fired up but would only idle. I limped to a spot where the tow truck could easly pick me up. After seeing these codes, I'm guessing it's the VP44. Does anyone have any suggestions before I spend the kids' Christmas money?

 

[johncameron]

Vp-44... ... ... ... ... ... ... ... ... ... ... ... ... ... ... .

 

[rkressg]

The 1688 and 1689 codes typically point towards an electronic failure of the VP44. An original VP44 on a 99 with that many miles is very rare, but does happen.

Before you go overboard, change your fuel filter. Make certain that the truck has Fuel in it (and that the gauge is not broken). I am assuming that you have good fuel pressure??? A new LP does not necessarily mean it works.

-Rich

 

[bigredblur]

Sorry for the slow reply. My internet at home is down. I don't tow anything and I hardly ever haul stuff so I can understand how I've gotten away with the original for so long. I do have fuel pressure after the filter. It's about 8. 5 psi. But when I step on the peddle, the poor truck just wants to die.

 

[bigredblur]

I ordered the VP44 from mwfi. I guess I can start taking out the old VP44 and then wait till the new one arrives. I watched these videos so I think I can handle it. My only problem will be the cold weather.

As far as codes are concerned, MWFI's site says

A current P1688 always means that the pump is bad, there is no further diagnosis required

. I'm content with this because of the age of my truck and my desire to start doing more fun stuff. Once I have a new pump, let the fun begin!

 

[SHobbs]

One thing that might help ya out. You do not have to remove all the injector lines. Cylinder #6 is hard to get to and can stay attached to the injector as well as the cylinders 3 and 5 that are with it. Just remove these lines from the back of the pump and loosen the hold downs so they will move and push them gently toward the block to slide the pump back and out. They will move enough to get the pump out. Cylinders 1, 2 and 4 need to be removed from the pump as well as the injectors.



I had a Cummins tech tell me about this little time saver which really helped me. If you remove the line from injector 6 you also have to remove the rear engine lifting bracket which is a pain. Also if the crankshaft position sensor is in the same place as mine you might see what the cost is for a replacement. The CPS on my truck is between the VP44 and the block, hard to access with the pump in the way. It is not a bad job and took me 3 hours my first time. Also another MUST, be sure that the keyway on the pump shaft is at the 12 O'clock position before removing the pump, you do not want the woodruffs key falling into the front of the motor. Have fun

 

[bigredblur]

Thanks for the tip! I was wondering about that because I read the same thing in the instructions on the MWFI site. I was also wondering about that sensor. Is it the CAM position sensor or the crankshaft position sensor? I remembering reading about both of them on my year model truck.

 

[SHobbs]

The crankshaft position sensor is the one between the VP44 and the block on my truck and the camshaft sensor looks to be just below the VP44.

 

[hcpBILL]

So what is considered a normal life expendancy of a VP-44? Mine has only 58,000. I have used Stanadyne consistently since I got the truck @ 25,000 miles. The lift pump went bad 3 times but never to a point where I experienced a loss of power. Before that happened I managed to catch it each time. I now have a Holley blue down by the fuel tank.

Thanks

Bill

 

[bigredblur]

I was using PS Diesel Kleen for the longest time. I haven't bombed my truck and I don't tow anything and hardly ever haul stuff. This truck is a daily driver for me even though it's a dually. That may be the main reason it's lasted so long. VP44 life seems to vary with application. Tomorrow, I'll be replacing my bad pump with the reman. I will also install a Holley blue for the LP and use the current Carter as a backup. I really want to have a setup like Gary's with a walbro and a bypass. But as everyone knows, I just spent a wad of money so those mods will have to wait.

 

[bigredblur]

Well it's done. I installed the new pump and everything pretty much went as the videos said they would. There is one small note to add. The new pump had an oil of some sort in it for storage I guess. When I took off the caps and rotated the new pump for the installation, I got oil on the truck and me. It was a relatively clean job till that point. I would also point out that Diesel Dan's VP44 videos made this a very easy job. The one thing I did differently was leave the back three injector lines on the engine and just move them out of the way. It was a tad harder that way but not as hard as I think removing injector line 6 would have been. Also, the new pump from mwfi had a keyway installed on the new pump already.

Guys, this was not a hard job. It was expensive and it was long but it wasn't hard. Watch the videos and you'll be able to do it.