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Engine Specific Info and Questions => IDI Engine => Topic started by: phaetonv10 on December 30, 2008, 06:56:22 am

Title: Cold Start problems... have to push every morning
Post by: phaetonv10 on December 30, 2008, 06:56:22 am
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
Title: Cold Start problems... have to push every morning
Post by: bert on December 30, 2008, 07:19:12 am
are the glow plugs actually getting power? there is a fuse on the mk1 put a tester on and check that first
Bert
Title: Cold Start problems... have to push every morning
Post by: bvolks73 on December 30, 2008, 07:30:19 am
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?
Title: Cold Start problems... have to push every morning
Post by: phaetonv10 on December 30, 2008, 07:43:51 am
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????
Title: Cold Start problems... have to push every morning
Post by: zukgod1 on December 30, 2008, 07:59:57 am
Low compression?
Title: Cold Start problems... have to push every morning
Post by: zozie on December 30, 2008, 08:03:12 am
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.
Title: Cold Start problems... have to push every morning
Post by: phaetonv10 on December 30, 2008, 08:35:46 am
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????
Title: Cold Start problems... have to push every morning
Post by: Vincent Waldon on December 30, 2008, 08:53:39 am
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.
Title: Cold Start problems... have to push every morning
Post by: lildevil on December 30, 2008, 08:55:25 am
does it smoke white like a mother?
Title: Cold Start problems... have to push every morning
Post by: bert on December 30, 2008, 11:41:44 am
I see your in pakistan,does it get that cold over there?
Bert
Title: Cold Start problems... have to push every morning
Post by: Rabbit TD on December 30, 2008, 04:50:52 pm
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.
Title: Cold Start problems... have to push every morning
Post by: theman53 on December 30, 2008, 06:40:58 pm
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.
Title: Cold Start problems... have to push every morning
Post by: jtanguay on December 30, 2008, 07:05:08 pm
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???
Title: Cold Start problems... have to push every morning
Post by: phaetonv10 on January 02, 2009, 10:39:43 am
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?
Title: Cold Start problems... have to push every morning
Post by: theman53 on January 02, 2009, 04:41:44 pm
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.
Title: Cold Start problems... have to push every morning
Post by: jtanguay on January 02, 2009, 06:40:51 pm
just to be sure, pull vacuum on the out port of the pump to suck some fuel through.. suck a good amount to confirm no bubbles are coming.  then try to start.

you can have REALLY bad compression and still be able to start at 0C with good glow plugs.  you do need good injectors though... a bad injector or two will definitely make it near impossible to start.  

when you start it at low temp, does the motor catch, or sound like it wants to start? or does it just sound like a gas motor without spark?
Title: Cold Start problems... have to push every morning
Post by: Rabbit TD on January 02, 2009, 08:36:13 pm
One thing I haven't seen anybody mention was the cold start device.  I guess your car has one doesn't it and is it working?  My car starts a lot slower even in the Summer over here if I forget to use it when the engine isn't warm.  Maby your cable pulled loose and it's not working, just a thought.  More than likely it is compression though  :(
Title: Cold Start problems... have to push every morning
Post by: Smokey Eddy on January 03, 2009, 02:57:31 am
A little check list to help clarify perhaps?

Glow plugs get power when the key turns *check*

Are there air bubbles going to the injection pump on first starts in the morning?

Maybe try adding a block heater?

All else fails you could take the injectors apart (follow a guide posted here on the forum) and see if your nozzles are jammed stuck. You may need to replace the nozzles. They do wear out and as jtanguay mentioned they would make cold starting really down right STUPID and frustrating to deal with because it is relatively difficult to tell if you have bad nozzles... without it being brought to your attention first.

Does the motor while running have a bad knock? - put a screw driver to each injector while it's running, put the butt of the driver in your ear and listen to each one. If you have really bad nozzles you will hear a very clear "knock" sound. Like a clack sound that really just doesn't sound right. Or and injector/injectors that sound distinctly different than the others.

I hope that helps a little bit!

(ps, this problem + burning oil makes me think rings are gone but let's not jump hastily to big jobs here!)
(pps, the answer to jtanguay's question about what it sounds like when it's trying to start would be a good clue too! he really knows his vee dubs.)
Title: Cold Start problems... have to push every morning
Post by: phaetonv10 on January 05, 2009, 09:29:45 am
Hi again guys
My car has started to start now. The problem was the gp's. I took them all out again, two were not working. So replaced them and it cranked into life.
So thanks all for your help!!!