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Hi Guys, I was directed here from BigFish over on the cumminsforum.com 

 

My 01 won't start at all.  For the past few weeks it was not starting back up once HOT.  I pulled the fuse to the lift pump to see if it would then start when hot, to eliminate the possibility of a diaphragm issues in the vp44.  It would not start.  It did start the next morning and threw the code P0118, coolant temperature sensor.  I replaced that sensor, and everything seemed fine.  IT would start back up when hot after replacing that sensor. 

 

Then a week later at the diesel station, it did it again.  Would not start back up when hot.  I waited 20 minutes, and she fired right up.  I drove her home.  The  next morning she fired right up, drove 200 feet and stalled dead.  Then started right back up.  I checked for codes again, and only P0118 was there, so I cleared all codes and now she won't start at all.  Yes she cranks at fuel speed.  Yes the WTS light does come on, and I can hear the grid heater click off when the light goes out.

 

I've cleaned all battery connections, replaced one battery that was weak, checked all grounds I could find, cleaned the connections in the PDC.  I had the alternator tested and all the diodes and the rectifier is fine, so I know that didn't knock out the ECM.  The truck is out of Florida and very clean.  I even bled injectors 1 & 3 in case there was in there somehow and fuel came out immediately.   Of course I changed the fuel filter right after this first started a month ago.  I put a FASS lift pump on about 800 miles ago back in July as she had the retrofitted pump in the tank.  I also bought a new MAP sensor and put  that in.  No avail.  Not sure where to go or what to eliminate next.  Any help would greatly appreciated.  I'm a campgrounds in Rhinebeck NY for the summer with my camper If anyone knows of any diesel Guru's around here.  Hoping to leave in a few weeks and willing to pay for expert help. 

   

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  • Owner
4 hours ago, rjbest333@gmail.com said:

to eliminate the possibility of a diaphragm issues in the vp44

 

Rev 027 pump do not have a diaphragm. 

 

4 hours ago, rjbest333@gmail.com said:

checked all grounds I could find,

 

The only ground you need to worry about is the passenger side battery terminal. You might consider the W-T ground mod.

 

What is your fuel pressure? Cranking, idling, highway speed and WOT?

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Fuel pressure at idle is 18 PSIWOT while taking off from a stop sign I can get it down to 10 PSI.   Usually about 15 psi at highway speeds.  While cranking just now its at 16 PSI while attempting to start up.   WOT while idling....If i remember correctly I believe it was 15 ish. I tested this after putting in the FASS.  That was back in May.  No I have not tried hot-wiring the VP44...  I've never heard of that.  I'm used to a 12valve.  This is the first 24v truck I've owned.    

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  • Owner
8 minutes ago, rjbest333@gmail.com said:

Fuel pressure at idle is 18 PSIWOT while taking off from a stop sign I can get it down to 10 PSI.

 

Too wide of a pressure swing. The pump is too small or the fuel lines are too restricted. Max swing should be only about 4 to 5 PSI. Even my 13-year-old AirDog 150 only has a 2-3 PSI swing from idle to WOT to well above 80 MPH.

 

8 minutes ago, rjbest333@gmail.com said:

While cranking just now its at 16 PSI while attempting to start up.

 

Cranking pressure is way too high. Pump should be modulated by the ECM for a 50% duty cycle and floating a mere 7 to 12 PSI normal while cranking. Since your pressure is this high it will cause the hard start hot problem. Check your power make sure you hooked up to the ECM and getting ECM modulation.

 

My pressures:

 

Idle 17 PSI

WOT: 15 PSI

Cranking 10-11 PSI bouncing. 

Edited by Mopar1973Man
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Thank you for the fast response.  When I first turn the key on I get that 2 - 3 second burst from the lift pump.  I assume this is from the ECM telling it to do that correct?  Power to the lift pump is going through this relay ( picture attached )  One hot line to the battery, and another coming from the original 2 pronged plug on the side of the block for the original lift pump that was there.  

unnamed (4).jpg

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  • Owner

When the ECM boots up and first up that normal to see that 1 to 2-second burst from the pump. I see at least you do have a protection relay and fuse setup so you have to have either FASS or AirDog. Still your pressure swing is too wide you need to look over the plumbing. Another thing I forgot about is when was the last filter change? This might impact the pressures too. Do you have the Adjustable pressure regulator or the old school ball and spring?

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Yes I have a FASS pump.  I bought a kit to replace all the banjo bolts.  Will take care of that once running.  Thank you for that.  

 

I changed the fuel filter about 3 week ago when this first started.

 

4 hours ago, Mopar1973Man said:

Do you have the Adjustable pressure regulator or the old school ball and spring?

I am unaware of an adjustable pressure regular... Would this be on the FASS ?  I don't know what the old school ball and spring is. 

 

 

Should it start without the lift pump running at all?  At 0 PSI ?  I pulled the fuse and tried this.  No luck. 

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Thank you for all the replies and help.  Much appreciation.

 

Yes I still have the stock lines and banjo bolts.

 

Is there a way to lower the PSI while cranking at start up so its not at 16 psi while cranking?  Seems odd this wasn't an issue for months and now all of a sudden it is.  Also It has never stalled on me in the 2 years I've owned it.  It stalled after driving 200 feet the last time it ran.  Then started right back up.  Could that be related to whatever is going on?

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1 hour ago, rjbest333@gmail.com said:

 

Is there a way to lower the PSI while cranking at start up so its not at 16 psi while cranking?

There is a delay relay mod or you can actually buy a relay with a built-in delay already. Sounds kind of confusing I know. 

But if your truck starts with half a crank like it should, there really shouldn't be a problem starting.  plus ECM Cycles power to lift pump so it's not going to be full pressure till the engine does start

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1 hour ago, rjbest333@gmail.com said:

Seems odd this wasn't an issue for months and now all of a sudden it is.  Also It has never stalled on me in the 2 years I've owned it.  It stalled after driving 200 feet the last time it ran.  Then started right back up.

 

Sucking air into the system possibly? Suction lines will not leak outwards. They continue to draw air in and never show any sign of leaking. Now @JAG1 has a trick of using a shop vacuum where you hook up the hose for blowing. This should push enough air into the fuel tank to keep pushing fuel in the lines to hopefully push it out your leak. 

 

If this is not enough pressure you can use compressed air with a blowgun and a shop rag and put 1 to 2 PSI worth of pressure in the fuel tank hopefully so a second person can spot the fuel leak. 

 

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I looked over all the fuel lines and tightened the all the banjo bolts and clamps.  Unfortunately I don't have access to an air-compressor where I am at, but I'm looking for one.  I bled injectors 1,3 and 4 and fuel shoots out with good pressure pressure on each line.  However noticed what I thought was some moisture in the fuel as I watched it ran down the block.  I then drained the fuel tank today, and put 10 gallons of fresh diesel in with Clear Diesel Fuel and tank cleaner to remove any possible water.

 

I then bled injector lines 1,3, + 4 again with no better results.  

 

I also tried just a touch of ether today twice, and she wanted to start right up, but would not.

 

She is definitely getting fuel to the injectors.  Are there any electronic shut of solenoids I could check?  Any other sensors that might be keeping it from starting up, with out throwing a code that they are bad?  Thank you for all the help guys, much appreciation.

unnamed (5).jpg

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The ddrp`s like the op has do have a ball and spring . Its assessable if you remove the 3 allens  on the aluminum mounting plate.

Ive had the old black ball they used to use swell and cause it to stick , was causing readings at idle of 23 lbs

They use a white ball now, still can get stuff on it.

Its a PIA to pull it from  the block to check

If I didn't own two of them , I`d get an air dog ASAP , mine is on the frame rail , bought the first a log time ago , second when I sent the first in for repair

Next time I pull my flat bed off I`ll probably change to a draw straw and air dog or what ever is best at the time

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3 hours ago, rjbest333@gmail.com said:

unnamed (5).jpg

 

There isn't much on the PS inventory I would even suggest using in your fuel tank. Most of that stuff is junk. If you have algae problem I suggest you just pull the tank down and clean it out then trying to kill the algae and filter it out. If the fuel is questionable I suggest just dumping it and starting over. 

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Yeah I got 10 gallons of diesel the last trip home, drove about 8 miles and shut it off.  Hasn't started since.  So yesterday I drained the tank and put 10 gallons fresh in with the PS additive just in case.

 

Still wouldn't start.

 

Is this a possible ECM issue?  With it not starting up when hot, and now just not starting at all ?  It is getting fuel to the injectors.

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