No start....battery issue? - Troubleshooting - VWDiesel.net The IDI, TDI, and mTDI source.

• No start....battery issue? by shelby987 on 29 Feb, 2012 06:52
• A quick history of my car, I have a 1.6l NA diesel that has been sitting for ~a year.  I bought a brand new battery the other day, cleaned the car up, jumped in, cycled the glow plugs twice, pulled the IP advance handle and she started on the first try!  No hesitation, no smoke (about 55 deg F), ran and sounded great!  I let the car get just below operating temp, and shut it down.  While doing my button up I noticed the battery didn't fit properly in the mounting brackets....brought it back to the store and got a new battery, that battery had a 1/11 sticker on it, so I dropped it off to Autozone for a full 1.5 hour slow charge.
  
  NOW, with the correct battery, the car does not want to start, if I get it started, it will run for 10 seconds with lots of smoke, and will eventually slow to a sputter....since it starts and smoke I am thinking "plenty of fuel"....and since it ran fine two days ago I am thinking "No engine problems".....but I can't figure out how a simple battery swap has caused this issue.....once she is running the battery shouldn't be able to kill this engine right?
• #1 by 8v-of-fury on 29 Feb, 2012 09:34
• Definitely not a battery problem.
  
  What colour is the smoke? I think you have a fuel leak somewhere, usually the only reason for these engines to run ok then sputter and die. OR your tank is empty and your sipping fumes. lol
  
  With these engines only running perfectly is plenty of fuel, because they do not monitor air intake, the amount of fuel injected is in direct relation to rpms.
• #2 by shelby987 on 29 Feb, 2012 12:01
• I am aware of the rpm's being directly influenced by the fuel qty.....I have done some digging and I am wondering if my battery is not supplying 12V after start-up and that slowly closes the solenoid in the pump?
  
  I have a full tank of fuel, I have fuel at the injectors, and I have replaced all the return lines at the injectors.  I will be installing a clear hose to monitor for air bubbles unless anyone thinks my 12v drop to the solenoid is a possible root cause?  Again, started and ran fine for 15 mins. on previous battery.....I think a fuel leak would have caused a puddle or a loss of prime in the last year....and not over night?
• #3 by 8v-of-fury on 29 Feb, 2012 12:07
• No. The solenoid will work down to like 8 or 9 volts.
  
  It its fuel related. There its nothing else that it could be. Fuel, air and heat. No restrictions on air? It already ran so compression its at least alright. Gotta be fuel.
  
  I've had this similar problem when the pump press being starved for fuel on multiple engines and pumps.
• #4 by Baron VonZeppelin on 29 Feb, 2012 13:44
• By fuel leak, he mostly means a suction leak.
  
  It does sound just like a suction leak - letting in lots of air.
  And those don't always produce a puddle of fuel.
  
  It "could" also be a restriction.
  Even possible fuel filter failure.
  
  A clear hose from fuel filter to Inj Pump supply line is right thing to start with. Even one on the return too. Refill your fuel filter at the same time.
  
  (if its a Mk2) Drain off the water separator under passenger side at rear axle until its solid diesel fuel. But be careful loosening the knob to drain - they can break apart depending on its condition. Usually best to delete them anyway - but probably would rather do it when you are prepared - instead of an emergency.
  
  You just woke up a sleeping potential problem, and now it wants to be your next nightmare. Probably a simple fix, once its diagnosed.
  
  Next time you get it running - turn on the headlights - and see if they stay bright. A voltage meter gauge would be helpful too, of course. But the headlights will tell you a certain amount.
  
  What kind of car / year model is it ?
• #5 by 8v-of-fury on 29 Feb, 2012 13:51
• Yes sorry, I was typing it out on my phone so I didnt go in to great great detail.
  
  When I said a fuel leak, and when any one does on a diesel they are more than likely meaning an "air" leak. As fuel very rarely leaks out but the air leaks in to the fuel lines. The lines are at most times under vacuum. Whether it be from the pump pulling fuel all the way from the tank, or because the fuel wants to drain back to the tank but is being held by the pump when not running.
  
  A piece of clear line would be the first step here to see just exactly what is going on with the situation. Until then, we are just speculating with a few different possibilities.
• #6 by shelby987 on 01 Mar, 2012 06:50
• Update, I am planning on pulling the pump supply and return hoses and replacing them, can I use standard rubber fuel lines or do I need viton lines?
  
  The current supply line has a rubber hose from the filter that is connected to a crimp steel fitting, that connects to a very rigid clear hose (that has since turned brown).  Can both of these just be replaced with rubber?  Is the supply fitting to the pump a barbed fitting?  (It was late last night, and I didn't feel like pulling the hose only to find out I had broken something that was infact not a barbed fitting).
  
  Lastly, when I pull these lines, will the pump hold its prime?  What is the best way to re-prime the pump?
  
  I know I am getting fuel to the injectors because the return lines between the injectors were leaking on two injectors, which is what prompted my original line replacement.
• #7 by Baron VonZeppelin on 01 Mar, 2012 22:21
• So what kind of car / year model is it ?
  Does it have the preheat fuel filter with T fitting in top ? (88-92)
  
  Standard rubber fuel hose won't last long with Diesel.
  There is Diesel Rated black fuel line.
  But you can't see through it, of course.
  
  I do all mine , and most all that i service for others, just like this picture.
  Its about 10-20 cents per foot at Tractor Supply and Lowes.
  Vinyl Hose / Tubing.
  
  5/16" ID on supply, and 1/4" ID on return.
  I use 1/8" ID x 1/4" OD tygon on injector jumpers - and a new cap plug on the last nipple of #1 injector.
  
  The fitting on the Inj Pump is barbed - but you can slice the old browny nylon with a razor and hook onto it - like this picture.
  
  Getting fuel to injectors has nothing to do with suction leaks within the system allowing air into fuel stream, and creating temporary loss of prime while sitting.
  
  Clear fuel lines are the best money you can spend - and these are cheap.
  Tygon is better than Vinyl - but not always available on local level in the sizes you want.
  
  The Inj Pump will hold its own.
  But the supply line and filter will need repriming.
  Good idea to top off fuel filter with fuel while its going on.
  
  A 1man brake bleeder or MityVac vacuum pump hooked to the return fuel lines will pull a nice solid reprime of fuel. Whether or not air bubbles come into the stream as you reprime depends on the integrity of your lines and connections. Thats the beauty of transparent lines fore and aft.
  
  
  
  
• #8 by Smokey Eddy on 06 Mar, 2012 13:17
• I concur. Defo sounds like a fuel/air problem. Starting up could have jossled some stuff amiss.
  While your hands are dirty also check all the glow plugs.
  I know the ones behind the pump are a real pain to get at but if you can get the bus bar off them you can test them with a multimeter.
  Testing for continuity you should get a good reading on each one. If there is no continuity that plug has burnt out.
  Obviously you can't do this if the copper bus bar is linking all the plugs together.
• #9 by shelby987 on 16 Apr, 2012 05:10
• This was on the back burner for a while, but I got back into it yesterday.  On the advice of a diesel tech friend of mine, I pulled the fuel filter, filled it with fresh fuel, and reconnected all of my lines....just like the first time, she started right off that bat and ran great!  I thought maybe I had a gummed up filter....but it ran for about 15 mins. before she died again....so I am pretty sure my problem is in the supply to the filter.  Are there any other filters between the tank and the main fuel filter? 
  
  When I run this line from the filter back to the tank, where is the connection at on the tank?  Do I need to pull the rear seat to get to it?
• #10 by shelby987 on 16 Apr, 2012 19:25
• Just to close out this thread, I found the problem!  Today I swapped out the Tee fitting in the fuel filter for the supply / return from the tank to the filter.  The previous tee-fitting / check valve looked as if the glue that held the top half to the bottom half had given up the ghost.  When I was holding the fitting in my hand I could see that I could flex the two halves apart and I believe this was allowing a loss of prime.....again a full fuel filter would let the car run for 15 mins.....but once the filter was empty, she would sputter and die.
  
  Thanks for all the help everyone!  The rest of the hoses look to be in good shape, so I think that project will be on hold for a while.