Cold Start problems... have to push every morning - page 1 - IDI Engine - VWDiesel.net The IDI, TDI, and mTDI source.

• Cold Start problems... have to push every morning by phaetonv10 on 30 Dec, 2008 06:56
• hello there
  i need help guys... my car just doesn't start in the morning. i have to push start it everyday.
  i thought it was because of the glow plugs, but changed them all and did not work. it is still not starting. but once it warms up, it starts at half a crank.
  what could the problem be? help plz!!!!!
  thank u
  taimur
• #1 by bert on 30 Dec, 2008 07:19
• are the glow plugs actually getting power? there is a fuse on the mk1 put a tester on and check that first
  Bert
• #2 by bvolks73 on 30 Dec, 2008 07:30
• Do you have a block heater? Mine would never start in the winter unless it was plugged in but never gave me any trouble as long as it was plugged in, even if a couple glow plugs weren't working. I suspect my problem was low compression.
  Could your starter be dragging and not turning the motor over fast enough?
• #3 by phaetonv10 on 30 Dec, 2008 07:43
• yes the glow plugs are getting power... and all of them are working...
  and my car is a mk2, 1.6D NA. so it doesn't have a fuse....
  and i changed the starter a week back, its almost new, so it is turning the engine fast enough....
  anymore suggestion?
• #4 by zukgod1 on 30 Dec, 2008 07:59
• Low compression?
• #5 by zozie on 30 Dec, 2008 08:03
• What oil do you use?
  My mk1 starts first flip even in -16 and I never have it plugged in. Lst year I used 15-40 and it turned over very slowly. I switched to 0-40 Mobil 1 and it's perfect now.
• #6 by phaetonv10 on 30 Dec, 2008 08:35
• i use mobil 1, 5w 40.... but my car was burning too much oil so i put STP oil treatment.... could that be the reason its not starting?
• #7 by Vincent Waldon on 30 Dec, 2008 08:53
• Quote from: "phaetonv10"

  i use mobil 1, 5w 40.... but my car was burning too much oil so i put STP oil treatment.... could that be the reason its not starting?

  
  
  Wouldn't be my first guess, although if you are burning oil your compression may be too low for reliable starts when cold.
  
  Did you test for power at the glowplugs themselves or are you relying on the yellow glow plug light on the dash ?  Dash light unfortunately doesn't confirm glowplug power.
  
  If you are not getting power the first thing to check is the fuse... On an MK2 it's bolted to the firewall next to to the brake booster in a small black box with two thick red wires.  It frequently developed hairline cracks that are difficult to see.
• #8 by lildevil on 30 Dec, 2008 08:55
• does it smoke white like a mother?
• #9 by bert on 30 Dec, 2008 11:41
• I see your in pakistan,does it get that cold over there?
  Bert
• #10 by Rabbit TD on 30 Dec, 2008 16:50
• After you check the fuse and make sure the plugs are lighting up if that doesn't fix it you need to do a compression test.  I hope someone jumps in here with some minimum compression readings.  I don't know how low they will go and still start as I've never had one less than 425 and on my 1500's they were 500 right after a rebuild, I haven't checked this one yet I'm now putting together.  This is PSI, I'm not sure what they use in Pakistan.
• #11 by theman53 on 30 Dec, 2008 18:40
• low spec on compression is 375lbs, but I have a 1.6n/a that has 260 in #4 and it still starts.
  I had this problem in my flat red rabbit and it was a combination of slower starter, glow plugs, and a small leak in the return line that wouldn't leak fuel only would let the system depresurize overnight or after 5 hours. I had 2 starters rebuilt and wouldn't do it. I went and bought a new one and it started fine after that. Well I fixed the other stuff and still had trouble until I got the new starter.
• #12 by jtanguay on 30 Dec, 2008 19:05
• Quote from: "phaetonv10"

  hello there
  i need help guys... my car just doesn't start in the morning. i have to push start it everyday.
  i thought it was because of the glow plugs, but changed them all and did not work. it is still not starting. but once it warms up, it starts at half a crank.
  what could the problem be? help plz!!!!!
  thank u
  taimur

  
  
  

  Quote from: "bert"

  I see your in pakistan,does it get that cold over there?
  Bert

  
  
  at night it can get cold...
  
  i'm thinking its possibly the fuel system...  overnight the fuel will drain back a bit and it takes time for the pump to build the right pressure... i'm going through the same thing with my mTDI.  i KNOW for a fact it has excellent compression due to the fact that when i turn it off, it doesnt sputter or spin an extra revolution.  theres so much compression that it just stops right away.  when i let the car sit over night though, it takes 1-2 revolutions and sputters briefly and then clears right up.  doesn't do that for the rest of the day though.  and for the rest of the day it starts right up with half a revolution (I LOVE IT)
  
  with all good glow plugs, that thing should start right down to -15C even with crap compression (been there... done that...)
  
  i have some bad gp's that'll need changing for when temps reach -15C though... (good compression in the range of 500 psi will start at 0 without gp's just to let you know... and even lower for TDI's)
  
  so things to check on your mk2 are:
  
  - water separator in the rear (or just remove it)
  - check valve (not sure exactly where it is, but it can restrict the flow of fuel)
  - fuel filter
  - fuel lines (they can crack on the inside at a connection, and look otherwise okay.  best to take it off and inspect)
  
  get someone to start it in the morning for you and do a visual inspection of the fuel lines.  if you have a vacuum pump, put vacuum to the fuel return on the pump and suck a good amount of fuel through.  if she starts good, then you know where the problem lies (air in the lines somewhere)
  
  and btw, how did you confirm that the GP's are working?  did you visually inspect them through the injector holes, or just apply power, and assuming that the bus bar is getting power, that they are in fact working? if your car sits for say 1-2 hours and completely cools down, does it start right up???
• #13 by phaetonv10 on 02 Jan, 2009 10:39
• Thanks for all the replies guys
  I ve come to the conclusion that its low compression.
  I checked all the glow plugs individually, removed each to confirm and there is power in the rail.
  And there are no bubbles in the fuel lines, and my car doesn't have a water separator.
  And it gets close to 0 deg cel at night but that's not that cold, I think.
  That's about it!!!
  So I think I ve come to the right conclusion, right?
• #14 by theman53 on 02 Jan, 2009 16:41
• 0 Celcius is 32F so it is cold enough that if you local diesel supplier doesn't see the need for winter grade fuel it still could be a fuel problem. I would change your fuel filter just for fun and see if it helps. I don't know if it has been mentioned or not, but you could check your IP timing. If it is too far out of time you will have hard starts and if your fuel and everything else is not perfect with a slightly out of time engine and you might have this problem your having.