KenEng

Hi there,<br>I've got a 99 3500 24v 6sp that will start fine, but then if you run it and shut it off, it won't start again. If you use a little ether, it will fire back up and run fine - until you shut it off, and then it won't start. If you go out the next morning, it will start fine again. <br>I get no fuel to the injectors, no white smoke. <br><br>I replaced the fuel filter, and am wondering if you have any suggestions. <br><br>Thanks in advance. <br><br>-Ken<br>

danlit

When you first get in &amp; turn the key, how long does your pump cycle?<br>Did the problem start after filter change?<br>Also I wouldn`t be sparyin Ether at it!<br>How cold is it there.<br>Is your grid heater working, my guess is that its not.<br> Danny

Alan_Reagan

Yeah, Nix the Ether or you may wake up in the next time zone. If the grid heaters are working, there could be an explosion in the intake and do quite a bit of damage. Sounds like the lift pump is not supplying fuel to the VP-44. I did a post on lift pump rebuilds a couple of weeks back.

http://www.dodge-diesel.org/yabbse/i...;threadid=8212

It would be about a 45 minute job for you to pull the pump off and turn the gasket over. It may get you going until you can get a new pump..

KenEng

I'm assuming the heater's working since it will start just fine on a cold morning.<br><br>I went to the store and bought a suitable pressure gauge tonight, and will check the output pressure tomorrow. What is the spec for this pump? <br><br>When I 1st get in and turn the key, the pump might cycle for around 30sec.<br><br>-Ken

Alan_Reagan

The pump may be pumping but not be supplying enough pressure. You should have 8-12 lbs. BTW, have you changed the filter lately?

KenEng

Just changed the filter when the truck started acting up.

Alan_Reagan

Missed the obvious again. Feel around the top of the filter cannister and see if it is wet. Check it carefully. If it's wet, dry it off, bump the starter and let it prime (don't start the engine). <br><br>Then, open the filter cannister water drain valve and turn the key to on. Don't bump the starter. If the lift pump is pumping, it will blow fuel out of the drain valve so don't do this in the garage or your wife will have your a$$. Mine, too.<br><br>That won't answer your pressure question but will give you some kind of idea about whether the lift pump is working or not. <br><br>Sounds like either the lift pump is not working well hot or the VP-44 could be having a problem when it's hot. Let's hope it's the lift pump.

danlit

Sounds like your lift pump is losing prime, the pump should only run for 1-2 seconds at the most.<br>Check the cap on the filter housing or change the filter again.<br>with a Fleetguard or Dodge only..<br> Danny

KenEng

The lift pump will run when I turn the key on, and then quit about 30 seconds later. If I turn the key off, and then back on, it won't restart the pump. Sometimes if I bump the starter and then listen, the pump won't be running.

When the pump is running and I open the drain valve, the pump sound changes and fuel drains out of the filter. I still haven't checked the pressure - I'll leave that until tomorrow morning.

I'm thinking possibly that once the lift pump warms up, it looses pressure - the VP44's internal transfer pump is capable of drawing enough vacuum to draw fuel from the tank once the truck's running.

Alan_Reagan

Look at the post I mentioned above. It is a quick fix for lift pumps and since today is Sunday and nothing is open anyway.....

KenEng

A few more observations - <br>I hooked up my pressure gauge setup today between the filter housing and the VP44 inlet. When I cranked the engine, the lift pump would make and hold 13lbs of pressure. After it shut off, the pressure would drop back to zero in a matter of a few seconds, is this normal? I have a ball-valve on the outlet side of my gauge, so I know that the pressure is dropping back through the pump, or the filter housing. BTW, the filter housing is dry.<br><br>When the truck is running (at idle) the pump maintains 14psi.<br><br>Right now the truck will not start - even though there's 14psi @ the VP44 inlet.<br><br>Another thing - If I crank the engine, and then completely shut the ignition off, the pump will continue to run for around 10sec. Is this normal?<br><br>Thanks.<br>-Ken

Alan_Reagan

The pressure will bleed back down. The problem is beginning to sound like the VP44. The fact that the filter was changed may have nothing to do with the problem you are having.

Once the engine is cranked over or the starter is bumped, the lift pump will continue to run for about 30 seconds. I'm not sure how you can troubleshoot the VP44 yourself.

You could crack a couple of injector lines and crank the engine over to see if you are getting fuel to the injectors. You may be getting fuel but if the VP44 is bad, the fuel may not be delivered at a high enough pressure to overcome the pop off pressure of the injectors.

Make sure the water drain valve for the fuel filter didn't stick open a little. This has happened before and caused this problem. Just push the valve rod on the drain down with your hand. Don't depend on the spring mechanism to close it. I don't think this is your problem because you would be blowing fuel out the drain when the lift pump runs.

At this point, since I've been rambling as usual, do the following things:
1. Take off the fuel filter cover and make sure the cannister is full.
2. If the cannister is full, crack three injector lines, preferably 4,5,6 but 6 is a little hard to get to so do 3,4,5 if you wish. If the cannister is not full, something is blocking the fuel from getting to the filter.
3. Turn the key on and bump the starter. Let the lift pump run. Then do that again.
4. Now crank the engine over a few times and see if you get fuel out of the injector lines you cracked earlier. If so, tighten the injector lines back up.
5. Start the engine. Nurse the throttle until she runs smooth.
6. Let's hope this solves your problem.

KenEng

I agree, it's starting to look like it might be the VP44 that's at fault. Although I hate to say it.<br><br>This would probably be a good time to say as well that I've been reuilding injection pumps for quite some time now. (Bosch, AMBAC, Stanadyne, Denso, etc) I must say that the Bosch P pumps are my favorite though <br><br>I've been pulling my hair out over this problem for a while, and wanted to get an &quot;outside the box&quot; opinion before I start really tearing into things. <br><br>When I was doing my inlet pressure checks this afternoon, I decided to crank the truck just for laughs with the inlet hose to the VP44 disconnected. Low and behold the thing started. Well, I immediately shut it back down and reconnected the inlet line to the filter, and the truck wouldn't fire back up again. I bled the lines, and still nothing - good pressure from the LP though. So, I let it sit for 15 minutes and then tried it again boom - she starts.<br><br>That's one of the reasons I'm starting to lean towards something in the VP44 being bad. The problem is just so intermittant.<br><br>Any more ideas at all are welcome.<br><br>I apologize if I was misleading at all.<br><br>-Ken

BIGOKIE

What about something electronic? Crankshaft position sensor,ECM,Etc,Etc. I'm no guru but it is a thought. Maybe a oil pressure signal?????

Alan_Reagan

I'm assuming since there is no &quot;check engine lights&quot; that the problem is in the pump/fuel supply area. Ken, sounds like you've checked everything out. It's strange that it started with the inlet disconnected. That's almost like you have pressure from the LP but the fuel is not making it to the 44. So when you disconnected, whatever fuel was in the line was able to go through. I agree as I said earlier, it's sounding like the 44. Keep us informed.<br><br>One more thing. Dang I hate it when this happens. Bigokie might have a point. Why not disconnect the big connector on the back of the 44. Spray some contact cleaner or even WD 40 on it, and then reinstall that connector. Make sure to lock the slide lock when you do it. You don't have anything to lose. Good luck, Ken.