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Hey Names Corey, been coming to this site for a long while now and decided to finally join in with this "new to me" truck I've had for about 9 months. I've had a few 2nd gens and actually never had any problems until this one but Im wanting to get in back into shape and see how long it'll go. Ive read the forums long enough to know yall like the sigs filled out so got that squared away from the start. I'm needing some help guys since this is my first cummins to have problems with there are a few things im still not certain of and if you need to ask me some questions to help me out let me hear them.

 

First off, when I first got the truck on a trade the PO "said" it was a newer VP44 but had made up his fuel lines from lift pump to housing to IP out of some dern pneumatic hydraulic lines with about 6-7 different fittings, and drilled and taped a stock LP on one side to make it a standard thread. psi on the screen would show maybe 8 on idle and 3-5 WO. knowing that wasn't gonna cut it I saved up a bit of money and got the fass titanium 150 system and mounted it on the frame rail and wired it up to the window motor fuse. 

 

I'm am having some crazy start up issues. some days it'll bust off immediately, afterwards it'll take 2-3 cranks to bust, after that 6-7 cranks.. after that id have to shoot the starter fluid to it but it'll sit there and idle just fine everytime. I see 0-1 psi before I turn the key if eventually it starts up my alarm will go off showing low pressure then build pressure and be just fine. I've seen no leaks on returns (the t, banjo behind the head, and even put in a new return valve from VP). I like to know whats actually wrong with my equipment before I start throwing high dollar parts at it "new vp44" so I'd like yalls help with that.

 

I'm the new parking lot graffiti  artist with all the oil spots im leaving behind, after doing the crank case mod that left a big mess of its own, I've tried cleaning up down there so try and see where it's coming from "im thinking tappet cover" but I messed up my electric oil pressure sender/sensor with water I believe so I'm scared to take a pressure washer to it again sort of.

 

Which bring me to this question my oil pressure electrically is reading anywhere from 40-98 psi while driving and at idle at a red light will go down to 25-35. I did get water all over it while attempting to clean one day so maybe that's the culprit but honestly I don't remember my oil psi from before hand. If yall say I need a new one that's fine by me, gives me a good reason to just blast away all the oily mess down there and find my oil leak.

 

I think that's a good starting point for now, I want to get my truck starting up correctly and go for reliability without burning too big of a hole in my wallet but if I'll do what I have to.

 

Much thanks, Corey

 

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Welcome to the forum!

If you bump the starter to activate the lift pump what kind of pressure are you seeing? Does it come up right away or does it take a few seconds to build pressure?

Are you still running the same pneumatic lines the PO had or did you install new fuel hose from your FASS up to the injection pump? If not I would recomend changing it out as all those fittings could be a source to draw air from and cause an occasional hard start. Do you notice if it makes a difference if you park the truck with the nose up or down hill? Sometimes (but not always) that will be a good indication because if the nose is pointed down hill the fuel is less likely to siphon back into the tank as it would if the nose is parked up hill.

I am not familiar with the FASS wiring but imagine it has to be similar to the Air Dog, with a seperate relay and 12 volt source from the battery or altenator. How is your pump wired? Are you saying your using the power from the power window fuse as a trigger for the lift pump?

Also, I'm sure your aware but I gotta say it because everytime I hear someone use ether it makes me cringe.....be very careful when using the stuff! If it is cold enough for your grids to ignite you could potentially set a bomb off in your engine, and blow the intake clean off or worse yet damage the engine along with anyone standing nearby. Yes that is the extreme version of what can happen but it can happen. Not to mention the stuff is just plain hard on th injection pump. If I was in an emergency and HAD to have my truck running, I would disconnect the grid heaters and use it, but aside from that I don't use it at all. I would rather find the problem, and fix it, like your trying to do. Good luck!

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  • Owner

Oil pressure minimum limits is...

 

10 PSI at idle

30 PSI at 2,000 RPM's
 

 

Which bring me to this question my oil pressure electrically is reading anywhere from 40-98 psi while driving and at idle at a red light will go down to 25-35.

 

 

You passed the minimum levels.
 

 

I see 0-1 psi before I turn the key if eventually it starts up my alarm will go off showing low pressure then build pressure and be just fine.

 

 

I think your getting a loss of prime and got a air leak in the fuel system.

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No way I kept the hyd. hoses.. I used the fass systems hoses and drilled and tapped the side of a fitting close to the ip for fuel psi reading.

If I bump it it'll build pressure immediately with no waiting 15-18 psi, my wiring it to the window motor just means it wont be pumping fuel while turning the key over. I've tried the parking down hill thing a while back, it didn't seem to help.

Okay I wont worry about oil pressures then, as for the air in the line im still pretty stuck. Any chance you have a list of everything that could let air seep back into the system? I'll go down the list double checking and see if that'll cure my crank issue.

 

IMG_3867.jpg

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Some of the most common places to leak are the return lines. There is a banjo the comes out of the back of the head (pretty hard to get to) that will leak, as well as the return line tee that is kind of behind the fuel filter housing. Those 2 places are probably the most common places to leak so I would start there. Then I might check the fittings on top of the tank. Did you use a draw straw or something like that?

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Ive tried thoughs, just tighted them all,suppose I can just replace all the orings and washers seals, maybe one has a tear in it or something.

maybe the injectors o rings? what do you think. if that could be hurting me anyways.

I did, the Vulcan straw with the 3 ports.

IMG_2404.jpg

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Try taking the Banjo that comes out of the back of the head out and replacing the sealing washers. 

I had a similar problem with mine and it ended up being the vent for the tank. Test this by leaving the fuel cap loose. Then go about normal driving/ starting to see if it helps. If it does fix your issue you need to get the vent fixed or buy a new one.

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Two things:

 

1. Get the FASS on a switched 12v so when you turn the key, it primes the system. Put the FASS on a 12v hot and have it running/priming before you try and turn the truck over. If it turns over when the LP is feeding pressure to the IP, I'd say you need to get it put on a switched 12v circuit.

 

2. Disconnect the plugs from the senders you are having trouble with and hit it with a blast of water to clean it out, then take an air nozzle and blow dry the connections. Then put some di-electric grease on the connections.

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Per the Fass instructions(same for AD)you can wire straight to the battery for power and use the OE lift pump connection for a trigger on the relay. That way it comes on with the switch and is controlled by the ECM. You can also wire the power from the alternator if you cont want the connections on the battery. That comes from the AD instructions, but I did not see it on the Fass.

 When It is wired the above way you will get a short prime when the key is turned on and when you bump the starter(no engine start)you should get near a 25 second run of the lift pump. The Fass should have come with a wiring harness to do this. 

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Okay had the chance to get to the return banjo and checked the T as well, both looked in bad shape, banjo not having any "seal" material on inside washer and the Ts' seals torn to shreds, replaced washers on banjo bolt behind head and replaced T completely with a barbed T and a bit of hose and clamps. Although it defiantly needed repairing on those 2 I'm still left with a very hard start. it loves to crank up in the coldish morning but it's off and on every time thereafter. Sometimes easy to start sometimes wont want to at all. What else do yall fellas think it is?

Only thing I can think of that's left in my fuel system is injectors and Vp44. once it's up and running it runs great, I don't know, any suggestions?

IMG_3879.jpg

IMG_3881.jpg

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Theres multiple things that can be to check injectors or the VP44. I don't have much experience in troubleshooting the IP, but you could start by checking a few things if it were the injectors.

 

1. Fuel mileage take a dive?

 

2. Run rough when running?

 

3. Oil drop test on paper towel, for stuck injectors, etc.

 

It does not sound like an injector issue to me though. If anything else, the IP....

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Fuel mileage is great, runs and idles fantastic when it does finally bust off, and as for an oil drip test I got a leaky tappet cover I believe so I have a half dollar mark everywhere I stop.

 

dtc: in order they came out:

 

P-PCU

P-0645

P-0500

P-1693

P Done

P ECU

P-1693

P-1291

P Done

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:rolleyes::)

 

No... Take your dipstick, let a single drop of oil from it fall onto a single piece of flat paper towel. Watch the oil soak into the paper towel. If it expands into a quarter size drop and looks very pale, like its just a wet paper towel and not oil, thats diesel fuel in the oil. That is a cheap, easy way to see if your injectors are leaking or stuck open, etc.

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  • Owner

Another way to just remove all 6 injectors and have them pop tested.

 

As for Hex0rz oil drop method it does work but if you see it you best change oil too. Also you still don't know which injector(s) is causing this problem which removal and pop testing will do. But as cheap as injectors are it best to replace them all.
 

 

P-PCU

P-0645

P-0500

P-1693

P Done

P ECU

P-1693

P-1291

P Done

 

 

 

P0645

http://articles.mopar1973man.com/2nd-generation-24v-dodge-cummins/59-obdii-error-codes/206-p0645-ac-clutch-relay-circuit

 

P0500

http://articles.mopar1973man.com/2nd-generation-24v-dodge-cummins/59-obdii-error-codes/190-p0500-no-vehicle-speed-sensor-signal

 

P1291

http://articles.mopar1973man.com/2nd-generation-24v-dodge-cummins/59-obdii-error-codes/212-p1291-no-temperature-rise-seen-from-intake-heaters

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I've heard of a lot of people doing this but you could just replace the o-rings too. It's a square cut o-ring from what I've heard and Cummins does stock them.

 

When I replaced mine there were none in the tee. It was like a compression fitting without the compression rings. I dont know why it help as long as it did.

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  • 2 weeks later...

Well I tried out hooking up the fass the regular way with hot on battery instead of the window fuse this morning just cause I fixed all my return system and wanted to see if it'd work..No goodie. It will usually crank up for me in the mornings. While I'm cranking its giving it any where from 12-18 psi and it wont bust off to save my life. So almost being late for work I went ahead and wire-nutted it back to the window motor wire, went back to the no psi cranks and it busted off for me. I don't believe its my injectors, oil looks great and runs fine after starting.  Hard for me to put it in a shop right now cause I'm working out of town but I'm sure I have most of the tools I need to diagnose stuff. Any ideas on what I should check out next guys? seems the warmer this weather is getting the more trouble I'm in.

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when you installed the FASS system, did you use a diesel compatible thread locker? i found one at a local part store that was marketed for marine applications. i used it on all the threaded ports when i installed my airdog 150 and i personally believe that is why my truck holds a prime for over a day. if you suck air in, then you will have trouble similar to what you describe.  :2cents:  i'm not a mechanic, i just play one on TV....and i stay in a holiday express last night.

https://www.youtube.com/watch?v=7jo_x7ecIFg

just in case you missed the joke :lol:

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