harder to start with warmer weather - IDI Engine - VWDiesel.net The IDI, TDI, and mTDI source.

• harder to start with warmer weather by mudman on 11 Apr, 2009 11:45
• I recently bought a 97 golf diesel and when it was cold out (below 0)it only had a slight miss when driving and now that it is warm it is extremely hard to start, wont run without the cold start lever out and smokes really bad. any suggestions what to look for?
  thanks in advance
  Craig
• #1 by jtanguay on 11 Apr, 2009 13:47
• sounds like the timing could be off, or it has an air leak in the fuel system.  check for air bubbles in the fuel lines next time you start it.  if it gets harder and harder to start the longer you leave the car sit, then this is most likely the problem.
• #2 by mudman on 11 Apr, 2009 14:53
• thanks for the info, I just talked to the guy that sold it to me and he said that there was a fuel leak on the injector pump. He pointed out a part that faces the drivers side its silver with a rubber cover that comes off. He said it may be a pressure regulator???
• #3 by jtanguay on 11 Apr, 2009 18:39
• Quote from: "mudman"

  thanks for the info, I just talked to the guy that sold it to me and he said that there was a fuel leak on the injector pump. He pointed out a part that faces the drivers side its silver with a rubber cover that comes off. He said it may be a pressure regulator???

  
  
  that could be the aneroid vent.  if fuel is leaking from there then theres an o-ring gone bad inside, and apparently its tricky to replace.
• #4 by mudman on 11 Apr, 2009 20:17
• thanks a tonne for the help, I did a  search and it is atmospheric vent that is seeping fuel. Now I just need to find a place close to where i live to get it fixed if I cant I may have to try to do it myself.
  
  Craig
• #5 by Dr. Diesel on 12 Apr, 2009 17:11
• Two thoughts:
  I had a 1.6TD some time ago with SLIGHTLY bent valves. Cold started like the day it was born, but no chance when warm.
  
  Also, if your engine's a little tired and needs help from the glowplugs even when warm, it might not be getting that assistance due to the nature of the system. Temp sensor says "no need" to the plug relay. could be the temp sensor is faulty and says "no need" at below normal temps.
  
  Just as an experiment, when the engine is warm, use some suitable gauge wire and light the glowplugs directly off the battery for 15ish seconds and then see how it starts. If it starts nicely, you have a lead to follow to the answer.
• #6 by dieselweasel on 12 Apr, 2009 18:04
• You have symptoms of retarded injection timing.  Being a '97, it will be an AAZ.  CHECK THE CRANK SPROCKET ASAP!  When it starts to fail the timing will be thrown off...when it fails completely there will be major engine damage.  Of course it could be something else but being an AAZ I would be looking at the crank sprocket first.  I highly doubt your fuel leak is causing this.
• #7 by mudman on 13 Apr, 2009 12:23
• thanks for the extra info, I tried to start it today and when it finally started it would not run without my foot on the throttle, when it did the idle would "loap"
  I am new to the diesel scene, what do you maen check the crank sproket? is it the one under the cover where the timing belt is or the visable one that runs the ac and accessories? I am going to go check what I can right now .
  
  Thanks again
  Craig
• #8 by mudman on 13 Apr, 2009 12:41
• well i pulled the cover off the timing belt and the belt is loose, enougt to rotate the injector pump pulley about the equivelent of being off 1 knotch.
  I am going to tear into it more and try to figure out why it is loose
  
  Craig
• #9 by mudman on 13 Apr, 2009 12:58
• looks like the belt tensioner backed off, I guess I am going to have to replace the belt and reset everything...
  
  Craig
• #10 by zukgod1 on 13 Apr, 2009 12:58
• Loose?!!!  :shock:
  
  
  Is the crank pulley wobbling?
• #11 by mudman on 13 Apr, 2009 13:12
• it is hard to tell if it is wobbling, the belt was so loose that when I asked my wife to crang the engine over the belt was flooping all over the place.
  
  I am going to recheck the crank/cam and pump for the proper position then I am going to replace the belt
• #12 by dieselweasel on 13 Apr, 2009 15:37
• Quote from: "mudman"

  thanks for the extra info, I tried to start it today and when it finally started it would not run without my foot on the throttle, when it did the idle would "loap"
  I am new to the diesel scene, what do you maen check the crank sproket? is it the one under the cover where the timing belt is or the visable one that runs the ac and accessories? I am going to go check what I can right now .
  
  Thanks again
  Craig

  
  
  I mean the crank sprocket that drives the timing belt...the one under the cover.  Do a search on this...just type in crank sprocket or crank pulley and AAZ.  It is a very common failure on the AAZ.  Do yourself a favour and educate yourself about it.  Remove and inspect the sprocket.  The bolt holding it is very tight so you'll need to make a holding tool (easy) or remove the oil pan to block the crank.  Be sure to replace the bolt and torque it correctly.  If you don't have a Bentley manual at this point and are going to be doing jobs such as the timing belt, I strongly suggest you get one (I can hear everyone else chiming in on this point  :lol: ).  Not trying to scare you, just would hate to see your AAZ blow up!
• #13 by mudman on 13 Apr, 2009 18:23
• dieselweasel after i looked at the car I figured out what you meant so I re-installed the timing belt (the injection pump was off by 1 knotch on the belt) and the car is running now. I plan on bringing it in to have the timing belt,tensioner and the crank pulley replaced (it does have a slight wobble)
  
  I just want to that everyone that helped, the previous owner was convinced it was a issue with a fuel leak and thanks to help from here my car is running now and not dead at the side of the road  
  
  Craig