Archived 2000 24V Died in Driveway

[alaskax]

I was warming up the truck in fairly cold weather, no problem starting.

Then after a couple of minutes, my wife reports hearing it "chugging" a bit before stopping. The weather has warmed up, my new batteries crank it over fast, my FASS with recent filters is bringing in the pressure to the VP44, but it has not so much as "popped" since then, over a week ago. I'm thinking maybe the VP44, but would really appreciate a diagnostic approach of some sort... this is a new area for me. At the moment it's a boat anchor!

By the way, there are no codes set.

Thanks in advance...

John

 

[BGlidewell]

how many miles on the fuel filter?

 

[Hammer]

If it has fuel pressure as you stated,have you tried cracking a fuel line and seeing if it will start?. Have you also checked the starter relay in the PDC to see if thats also OK?... ... . Andy



P. S. -I was going to tell you if the fuel level was low enough with the FASS drawstraw you could have symptoms like your seeing. Its well noted already that when you use the FASS drawstraw you loose the last 7 gallons or so. Those of us who won FASS units will tell new FASS users that when the low fuel light dings,you better be at or close to a fuel pump or risk the chance of a walk.

 

[alaskax]

Do you mean cracking a fuel line at the injector while cranking, like to see if there is air in the system?

I'm confused about the starter relay- how would a bad starter relay kill the already running engine? I recently put in a new starter/solenoid, and at the time checked that relay. In any case, it cranks over like a dream. Is it something else you are getting at?

I have had the FASS for many years, the tank has lots of fuel, filter has about 1000 miles on it, and the fuel pressure gauge reads around 15 psi.

John

 

[jakprince]

I would check for trouble codes doing the key on off deal. There are like 3 codes if any of them come up then the vp 44 is toast

 

[alaskax]

Thanks, I'll try that, but I put my scan tool on it and no codes came up. But just in case...

 

[Sticks]

Start simple...

You do have fuel right?

Bump the starter to get the fuel pump in prime cycle, and crack open the VP44 fuel inlet banjo bolt to make sure you are getting good fuel, not foamy.

Crack an injector line or two and crank. Best if you have someone else crank while you watch to see if you are getting good pressure. READ - the fuel should squirt out around the jam nut, not dribble, and not foamy.

Visually inspect the fuel line connections between the VP and the tank for any wet spots, connections that have collected dirt and appear muddy/greasy.

Check your fuses. There are 2 in the PDC under the hood IIRC that can impact the VP44. Swap out the ASD (Automatic Shut Down) relay with another known good one.

Report back what you find, along with any codes you get (doubtful if you already put a scanner on it).

 

[Hammer]

Thank you for explaining that to him for me Sticks as I just got up to get ready for work... ... . Andy

 

[alaskax]

Yes, thanks indeed guys, I checked the fuse box but can only identify the fueling relay- don't see any related fuses. Any clarification here appreciated, but otherwise I think I have a plan to follow, and just so darn busy it may be a few days before I can get to it. Fortunately my Golf TDI is running!

 

[Sticks]

Fuse #3 - 20A, There is also a Fuel Pump Relay that should be swapped out as well as the ASD, and the other fuse I can not remember where I found it.

Generally I check all fuses when looking for a mystery bad one.

If you live in a High humidity area, check for corrosion at the fuse terminals, and any loose fuses.

 

[alaskax]

Well, I bled the low pressure fuel at the VP44, it looked good, then I electrically tested the VP44 by validating 12 V at pin 7 when ON and in START position. Passed that test. I've read that it the VP44 is getting fuel and passes that electrical test, then that's all it needs for the truck to run.

Then I decided to loosen the injector fittings to either bleed the injectors or see if there was adequate pressure. At first I thought it must be the pump since one inlet was barely dribbling, but then another one was pressurized little squirts, so I really wasn't sure. In any case, after bleeding another one, the truck ended up firing up after a bit of nurturing.

I'm convinced at this point that my FASS system is the culprit, since it has been "whooshing" for a long time now, with pressure going up and down, but the pressure has always at least been there. I think it just injected air into the VP44. I notice now after the fact that it's more "stable" but it's literally going to zero pressure for a few seconds. I guess it's time to invest in a new FASS(??), but at least I don't need a new VP... yet!

Thanks a ton for your suggestions guys!

John

 

[Sticks]

Check to make sure you FASS is not sucking air somewhere. Loos fittings, broken stand pipe, old and cracked fuel lines...

A quick and easy test is to get a fuel can full of diesel and run a separate line from the FASS into the fuel can, or as I like to call it, an IV bag, and see if your pressure and engine operation gets better.

 

[Hammer]

Before you invest in a new FASS call them and see where you stand warranty wise. You may be able to ship the faulty unit back and have a new one for just the cost of shipping,if you registered it when you made the initial purchase.

 

[icman95]

I'm on board with Sticks-while the FASS unit itself may be the problem, there could also be a line or connection that has a leak allowing the pump to suck air into the system. I had it happen to me on not only my Dodge, but a Freightliner as well. The Dodge had a bad O-ring on the fuel filter cap straight from the factory. It caused it to suck air into the fuel system. The Freightliner (also with a Cummins, but a bit bigger at 14 liters) had some older fuel lines that had rotted and started sucking air in. Caused similar problems to what you're describing. Hard to find and diagnose, but if it's the problem cheaper to fix.



Good luck.

 

[alaskax]

Again, thanks for the suggestions. Watching my pressure gauge slam back and forth has been driving me crazy, and it's consistent with the sound of the FASS pump whooshing. Was not really sure how to eliminate the possibility of it sucking air, but Stick's IV analogy makes sense. I'll try that next. Unfortunately, I already investigated warranty, but since I put the system in almost a decade ago, the 5 year thing is up! If I don't need a new FASS pump NOR the VP44, I'll REALLY be happy!

John

 

[DieselLady]

The wooshing sound is air, although I am sure you already figured that out. I do know that there is an O ring rebuild kit for these pumps. I got one with my Airdog and used it on my old 95 gph pump. fits perfect. But I would be looking or air being sucked in prior to the pump first. The IV bag is a really good idea. it will confirm that.
Good luck.