Hard to start when cold - white smoke at startup - page 1 - Troubleshooting - VWDiesel.net The IDI, TDI, and mTDI source.

• Hard to start when cold - white smoke at startup by wikdslo on 01 Oct, 2007 07:58
• Car: 81 diesel rabbit, low km.
  So I finished doing a headgasket, timing belt, tensioner, and putting on another injeciton pump with rebuilt choke cable seals.
  
  Since doing this, (and possibly before as the car was in repair most of the time) when the car is cold, i have to crank it a LOT to get it to start. Sometimes up to a minute of cranking, and then it will sputter slowly, then it will kick and finally it fires and runs rough for about 5 seconds then, it's good.
  Also when starting there is a big cloud of white smoke that comes out of it. When it starts and drives, there is no smoke.
  
  I read on here, that the smoke could be glow plug related.
  I have a bentley, does that tell me how to test them while on the car?
  
  When I have the car warm, even if it's been off for 2 hours. It still fires up perfectly, after only a crank or two.
  
  One thing I would also like to know, after rebuilding the seal on the injection pump for the choke cable assembly, is it possible I have the choke closed when open, and open when closed? Or soemething like that?
  This could be causing me to have it open the whole time while the car is off, then closed when trying to start if that makes any difference.
• #1 by jtanguay on 01 Oct, 2007 13:45
• well for the glow plug issue, the most reliable way of seeing if your glow plugs are working, is to either pull the injectors and turn the key on and check if they are glowing.  that can be a pain though because the injection pump is in the way  :roll:
  
  or you could run an amp meter to measure the current draw.  a bad gp won't draw much if any.  or just pull them all one by one and give them some juice.
  
  but before doing any of that, make sure that the power bus is getting juice when you turn the key.  you wouldn't want to feel like an idiot if its just a fuse or something...  :lol:  on my old diesel i disabled the gp's, and i could crank for a few minutes and it wouldn't fire, and a huge smoke grenade went off (really low compression) but then enabled them, and it fired after 3 cranks (this is around 5C or so)  
  
  as for the cold start thing, i think that it may be possible to have the internals screwed up as you described.   when timing, did you push the cold start in and time it to 1.00mm?  for the colder months try 1.05mm.  my car is approx 1.06mm and it fires up on a single crank each and everytime (but i'll report back when we get into subzero temps... thank god my work has plugs for the block heater!)
• #2 by wikdslo on 01 Oct, 2007 14:35
• Quote from: "jtanguay"

  well for the glow plug issue, the most reliable way of seeing if your glow plugs are working, is to either pull the injectors and turn the key on and check if they are glowing.  that can be a pain though because the injection pump is in the way  :roll:
  
  or you could run an amp meter to measure the current draw.  a bad gp won't draw much if any.  or just pull them all one by one and give them some juice.
  
  but before doing any of that, make sure that the power bus is getting juice when you turn the key.  you wouldn't want to feel like an idiot if its just a fuse or something...  :lol:  on my old diesel i disabled the gp's, and i could crank for a few minutes and it wouldn't fire, and a huge smoke grenade went off (really low compression) but then enabled them, and it fired after 3 cranks (this is around 5C or so)  
  
  as for the cold start thing, i think that it may be possible to have the internals screwed up as you described.   when timing, did you push the cold start in and time it to 1.00mm?  for the colder months try 1.05mm.  my car is approx 1.06mm and it fires up on a single crank each and everytime (but i'll report back when we get into subzero temps... thank god my work has plugs for the block heater!)

  
  
  I'm going to go check the circuit for the glow plugs shortly. I'll try hooking up an amp meter to them and check each as well. I'm assuming the process on that is in the bentley?
  
  And as for the cold start, yes, i had the cold start pushed in so taht it should have been closed. And timing showed 1.03mm. But if that is backwards, then i dont know what the timing is actually at.
  
  Thanks for the help.
• #3 by jtanguay on 01 Oct, 2007 15:43
• yep pushed in is proper way of doin it.  only way i could see that getting messed up is if you forgot to connect the cold start lever (so it basically does nothing) but i trust you connected it. right?  :lol:  :wink:
  
  im not sure what the bentley procedure is for testing GP's... i dont think they list using the amp meter to test the gp's.
  
  1.03mm is pretty good. i'd leave it there.
• #4 by wikdslo on 01 Oct, 2007 16:52
• Quote from: "jtanguay"

  yep pushed in is proper way of doin it.  only way i could see that getting messed up is if you forgot to connect the cold start lever (so it basically does nothing) but i trust you connected it. right?  :lol:  :wink:
  
  im not sure what the bentley procedure is for testing GP's... i dont think they list using the amp meter to test the gp's.
  
  1.03mm is pretty good. i'd leave it there.

  
  
  Yup, it's connected, it was just a matter of if it was not connected properly, or reinstalled incorretly so as to make it close when opening, and open when closing, if that is possible.. *shrug*
  
  Per the Bentley, it appears my glow plug relay is toastered.
  Here is how I checked, please tell me if i am missing anything.
  
  1. Connected voltmeter (or test light) at the #4 cylinder glow plug connection, turned key to on position and found that there was no power.
  2. Checked the inline fuse attached to the firewall, visually appeared fine.
  3. Removed relay and tested terminal #30 for constant voltage. -OK
  4. Checked terminal #86? for constant voltage when keyed on. -OK
  5. Checked connection between terminal #85 and #50 for connection - OK
  
  I believe that was what the bentley said to do. But basically I ran through all of the steps, and it appears that power is getting to where it needs to on the relay plug, but then is not passing through the relay.
  
  Thus... My relay has passed on into the next life.. So long little fella, you'll be missed.
  
  Now, will keeping the car plugged in overnight help me not damage the glow plugs?
  Anything I can do to keep from damaging them?
  
  I'm gonna hunt me down a new relay asap, suggestions?
• #5 by jtanguay on 01 Oct, 2007 22:44
• well if its a low budget car, then simply rig up the glow plugs to turn on via a switch.  get a house light switch (rated for 115v it won't die).  leave the switch on for about 10 seconds or so.  
  
  dont worry about damaging your gp's when not using them.  just worry about bad starts  :lol:
• #6 by wikdslo on 02 Oct, 2007 04:31
• Quote from: "jtanguay"

  well if its a low budget car, then simply rig up the glow plugs to turn on via a switch.  get a house light switch (rated for 115v it won't die).  leave the switch on for about 10 seconds or so.  
  
  dont worry about damaging your gp's when not using them.  just worry about bad starts  :lol:

  
  
  I think I'm just going to replace the glow plug relay. I see no reason why not to.
• #7 by BlackTieTD on 02 Oct, 2007 08:23
• two things to try:
  
  - get the relay from a junkyard or used car... might as well grab a few for the toolbox.
  
  - i think the fuse is 50 amp. either use the same fuse, or get another 50 amp fuse and then hook the glowplug bus bar directly to the + terminal on the battery with the fuse in line
  
  + --- FUSE --- GP_BUSBAR
  
  hook it up for about 10 seconds, then have someone crank over the car, or do it with a screwdriver across the starter terminals if you're ok with that.
  
  this will mimmick 'proper' operation of the GPs.
  
  note: when i do this i never use an inline fuse and i've never burnt out a plug like that, but do what you'd like
• #8 by wikdslo on 02 Oct, 2007 09:29
• Quote from: "BlackTieTD"

  two things to try:
  
  - get the relay from a junkyard or used car... might as well grab a few for the toolbox.
  
  - i think the fuse is 50 amp. either use the same fuse, or get another 50 amp fuse and then hook the glowplug bus bar directly to the + terminal on the battery with the fuse in line
  
  + --- FUSE --- GP_BUSBAR
  
  hook it up for about 10 seconds, then have someone crank over the car, or do it with a screwdriver across the starter terminals if you're ok with that.
  
  this will mimmick 'proper' operation of the GPs.
  
  note: when i do this i never use an inline fuse and i've never burnt out a plug like that, but do what you'd like

  
  
  Good call. I'll see about getting an inline 50 amp fuse and give this a shot. Probably not a bad thing to have kicking around for other random tests anyhoo.
  
  I will definitely give this a shot tonight and report back!
• #9 by wikdslo on 02 Oct, 2007 15:34
• Quote from: "wikdslo"

  
  Good call. I'll see about getting an inline 50 amp fuse and give this a shot. Probably not a bad thing to have kicking around for other random tests anyhoo.
  
  I will definitely give this a shot tonight and report back!

  
  
  So, I got a little lazy, and a little crafty.
  
  Rather than run another 50amp fuse, I just made a switch which connects + on the battery to the input (from the fuse panel end) of the existing circuit, where it connects to the 50amp fuse.
  
  So it's still fused, and using the same circuit.
  
  Turned that bad boy on. Turned the key to on, waited for the light to go out, and then cranked. Fired up after just 2 turns and ran quite well.
  Then I ran aroudn and shut the switch off.
  
  Everyone cheered!
• #10 by BlackTieTD on 02 Oct, 2007 16:33
• awesome! funny, i was going to suggest putting a temporary switch on the existing circuit exactly as you described but i didn't want to go back and type that out!  :lol: nice work
• #11 by wikdslo on 02 Oct, 2007 17:40
• Quote from: "BlackTieTD"

  awesome! funny, i was going to suggest putting a temporary switch on the existing circuit exactly as you described but i didn't want to go back and type that out!  :lol: nice work

  
  
  Oh but you practically did suggest that!!!!
  
  Actually, I think someone else did. But you both gave valuable input which helped me narrow down and confirm what the bentley suggested. And now I don't have to kill the starter or anything else cranking this biatch for 90 seconds to get it to start..
  
  So, for that I thiank you kindly sir. And same to jtanguay. Both of you are close enough to Toronto (Scarborough) that if ever you are down here, please let me know so I can share my hospitality and have you over for some bbq and brewskies..
  
  Cheers gents'
• #12 by jtanguay on 02 Oct, 2007 18:21
• Quote from: "wikdslo"

  Quote from: "BlackTieTD"

  awesome! funny, i was going to suggest putting a temporary switch on the existing circuit exactly as you described but i didn't want to go back and type that out!  :lol: nice work

  
  
  Oh but you practically did suggest that!!!!
  
  Actually, I think someone else did. But you both gave valuable input which helped me narrow down and confirm what the bentley suggested. And now I don't have to kill the starter or anything else cranking this biatch for 90 seconds to get it to start..
  
  So, for that I thiank you kindly sir. And same to jtanguay. Both of you are close enough to Toronto (Scarborough) that if ever you are down here, please let me know so I can share my hospitality and have you over for some bbq and brewskies..
  
  Cheers gents'

  
  
  hmmmm i can't say no to bbq and brewskies
• #13 by burn_your_money on 02 Oct, 2007 22:09
• Jonas throws a mean BBQ, highly recommended  
• #14 by wikdslo on 03 Oct, 2007 04:28
• Quote from: "burn_your_money"

  Jonas throws a mean BBQ, highly recommended  

  
  
  Thx chum, I try