Saturday had a little trouble getting the truck to start.

Checked for codes with my handy dandy DRB3 and sure enough crank position sensor showed up .

Ordered 1 and it will be in tommorow afternoon at the local dealer.

Figured I was okay to run some errands with it today...not so much.

Quit all together at a local muffler shop...grrrr.

Figured might as well get it floated home, no problem.

Home in the yard I do a bit of diagnosis and think it strange that I have 1 lb fuel pressure.

So I use a piece of harness and jump the pump direct...no sound. 

Pull the pump and find the wires burnt right off at the pump.

Must have chafed or something but I dont know why. Nothing there really to cause that.

Now to see if I can solder on a couple new ones. Pump was not stuck either, very good shape inside. 

Looks like new. Anyone else see anything like that.

Might not be a crank position sensor after all...false starts set a code maybe?

 Regards Chris

If the wires did short out somewhere, wouldn't it have blown the fuse? Seems a little odd to me that it could have gotten hot enough to melt the wires off. Unless there was too big of a fuse used....

...time for a Fuel Boss!

The wires were burnt or pinched right where they come out of the pump motor.

Looks like its been going on for some time

Well, I got the rewiring done but can't seem to get it to hold any fuel pressure.

Wont start and wont hold pressure when you let off the key.

Falls back to 1 lb in a second or 2.

Must have a leak on the suction side I guess.

Never had this truoble bleading it before.

Regards Chris

Not suppose to hold pressure after the pump shuts down.

I thought the pressure held for a few seconds. Never really paid much attention before I guess.

 Any chance the false start is what messed up the crank sensor and threw the code.

I pulled the starter and removed the sensor.

Hopefully thats why I can't seem to bleed the system.

I have fuel to the injection pump but not past it it seems.

Regards Chris

I should have asked if the bad cranksensor (or wire to it) can keep the truck from running.

 Regards Chris

Yes a bad crank sensor will prevent the VP44 from firing because the ECM doesn't see the engine turning so the VP44 won't fire.

Well I got and installed the new crank position sensor.

No start. Checked for codes with the DRB3 and ...oh oh shows the dreaded p1688

I cleared it and its not back yet but the truck is still not running. 

Only seems to have pressuer on #5 fuel line. 

Any ideas whats up.

Should I be ordering a new injection pump...yikes.

Regards Chris

I'm not an expert on vp but from what I heard and read usually a seized rotor if you get fuel only out of one line, meaning new vp is needed. Sorry.

Seized rotor...hmmm.

The DRB3 shows crankshaft rpm, camshaft rpm but no rpm for the injection pump.

Seems like its done doing its rotating I guess.

Regards Chris

I have never heard of a seized rotor on a VP44.

 

Ed

While I was doing some testing the scanner showed that the crank was turning, the cam was turning but the IP was not. 

I cleared the P1688 code and waited a while and re did the scan. Pump would turn same rpm as crankshaft. 

Not sure if I just read it wrong or what.

Still wont go and if I keep cranking the P1688 comes back.

I have to say that the scanner shows a lot of info and I am still learning what it capable of.

Only have fuel from line I think.

Regards Chris

I am thinking a new pump from DAP and maybe some injectors while I have the hood open.

Someone was into it before, the turbo is an HX at least the part with the tag is.

I thought it was kind of peppy on the highway.

Any suggestions about injector size...I asked before and I think I was going with RV275, might go up a bit more.

 Regards Chris

P1688 reads "Internal Fuel Injection Pump Controller Failure (found on Google) Generally not a good thing. Probably looking at a pump no matter what.

I would look at the RV275s as they are a nice upgrade and also seem to assist with mileage too.

I just put 60hp from dap in and I had 75hp before. Noticeable power difference but not huge, next time I'm going back to 75hp, will try these out for a while I think I did gain 1or2 mpg but I also put a bit smaller tire so... I know for sure rv275 won't satisfy me anymore and in future if I get bigger turbo I'm looking at 150hp maybe. But as of now I'm not disappointed with 60hp just when you had something bigger, hard to go backwards.

As for injectors, anything up to about a 75hp will run good with a stock turbo. You might have to watch the EGT's a bit more but it wont be bad. I would personally stick with a 40-50hp sticks. Good power and mileage too.

 

As for the VP, I read something somewhere (maybe on bluechip's site) that the early rebuild VP's and also the stock VP's had a slight problem with the rotors being machined incorrectly. There were some problems with them seizing up or just not turning smoothly. The newer rebuilds seemed to have fixed this problem.

 

I will try to find where I read that...

Right off of Chip's diagnostic page:

 

 

 

If the engine won’t start, AND YOU HAVEN’T OPENED ANY FUEL LINES OR REPLACED THE FUEL FILTER SINCE IT LAST RAN, and you have either or both a 1688 or 1689 code, the truck will never start until you replace the injection pump, 99% of the time. If you want to be 100% sure of your diagnosis, follow the No Start diagnosis below. These codes indicate either a serious internal mechanical failure, such as a seized rotor, or that the computer on the top of the Injection Pump is not communicating with the ECM, thereby turning on the high pressure fuel to the injectors.

I spent a bit of time reading Chips diagnostics and looked at Michaels as well.

Spent a few minutes here and there this morning and pulled the injection pump off.

I was thinking it would be really difficult. Not to bad at all really.

It just happened that the tilt load wrecker dropped it in the perfect spot for the morning sun to light things up.

I usually prefer to work inside on this sort of thing, but today was an exception. 

Now to wait for a pump to show...with some injectors of course.

 Regards Chris

Made the call to DAP and the injectors and pump have been ordered...now to sit down and relax a bit.

Will be at least a week perhaps more getting here. 

Ah the suspence is gonna be difficult.

Regards Chris

My little box of parts crossed the border today...25 pounds of goodies.

Customs sure takes their time with my stuff.

Oh well if I am real lucky it will be here for the weekend install.

Most likely it will show Monday.

Chris