running cold and poor starting

whiterabbit7

Veteran Member
Joined
Feb 17, 2003
Location
Joplin,MO
TDI
2000 Golf GLS 201k miles
I think I am having two separate problems. The car has started always running cold. About one notch below 190F. Should I be worried about this? What do I do?

Second. The car doesnt start well. When starting after its been sitting overnight, it takes a little extra cranking and then runs poorly for the first 1-2 seconds. It seems like this problem was a lot worse when it was colder out. Could this be a leaky injector? I have new nozzles to install. Will they likely fix this problem?
Thanks
Dan
 
Last edited:

bluesmoker

Veteran Member
Joined
Jun 7, 2006
Location
Maple Ridge, B.C.
TDI
2004 pd 5 speed tip
check your battery, it could be weak (not enough amps to run the glow plugs)

the glow plugs or harness could be bad, search the forums for "glow plugs"
 

whiterabbit7

Veteran Member
Joined
Feb 17, 2003
Location
Joplin,MO
TDI
2000 Golf GLS 201k miles
The battery, glow plugs, harness, 180 relay, and 109 relay are all new. Glow had quit working before, but that problem has been fixed. From what I can tell this is not related to the glow plugs. This may take the best minds here.
 

dieseldorf

Top Post Dawg
Joined
Oct 11, 2000
Location
MA
TDI
ex- 1996 wagon, ex-2000 Jetta
Dan, do you have VAGCOM? Can you make some basic checks for DTCs and verify the coolant temp sensor is doing its job?
 

Traildog

Well-known member
Joined
Oct 15, 2002
Location
Western Connecticut
TDI
'96 Passat wgn green, '99.5 Jetta silver (son's), '06 Jetta pkg2 wheat beige (wife's)
What DD said:
VW programmed in a "flat spot" at 190* in the guage of @7 degrees either side of 190. I guess so that people wouldn't freak when the guage went over 190 climbing a hill and under 190 coasting down the other side. Your reading below 190 makes me think you're running substantially below that.
Since the CTsensor controls both the guage and the ecu:
A its bad, giving the guage faulty info, and possibly the ecu as well.
B its good, and you're running cold because the thermostat is sticking open. Your engine isn't running in its sweet spot either.

I'd replace the CTS first, and see if you read 190*. If the CTS was feeding erroneous info to the ecu as well, you may have solved both problems.
 

whiterabbit7

Veteran Member
Joined
Feb 17, 2003
Location
Joplin,MO
TDI
2000 Golf GLS 201k miles
The coolant temp sensor has been replaced. Because during the winter the glow plugs werent working and the car wouldnt start. I dont have access to VAG-com. Frank06 is about 45min away. I guess I'll have to go use his services. I need to get my new PP nozzles installed anyway.

What are DTCs?
 

Traildog

Well-known member
Joined
Oct 15, 2002
Location
Western Connecticut
TDI
'96 Passat wgn green, '99.5 Jetta silver (son's), '06 Jetta pkg2 wheat beige (wife's)
Diagnostic Trouble Codes

Since the CTS is new, getting connected to Vag-com to read the actual temp as well as seeing what else is happening seems the next best step. Hopefully nothing serious.
 

greengeeker

Vendor
Joined
Feb 8, 2006
Location
Cambridge, MN
TDI
2002 Jetta GLS
not getting up to temp: could be your thermostat is bad or your temp sensor is bad out of the box (happens a lot on the cheaper parts)

hard start: given the parts you already replaced I would think you have a small air leak in your fuel system, either injection pump or lines. Does your golf have a clear line inbetween the filter and IP? If so, watch it in the morning for large air bubbles.
 

Bob_Fout

Oil Wanker
Joined
Sep 5, 2004
Location
Indiana
TDI
2003 Jetta - Alaska Green (sold) / 2015 GTI 2.0T
Hard starting and poor initial running could be timing too.
 

mrGutWrench

Top Post Dawg
Joined
Aug 29, 2002
Location
Carrboro, NC
TDI
'03 Jetta Wagon, 5-speed, 563K Miles (July '23)
greengeeker said:
not getting up to temp: could be your thermostat is bad or your temp sensor is bad out of the box (happens a lot on the cheaper parts) (snip)
__. Yes, that was my first thought. This just "feels like" temp sensor for both symptoms.
 

JASONP

Top Post Dawg
Joined
Feb 24, 2008
Location
Guelph
TDI
2015 Golf TDI Comfortline 6spd
Bob_Fout said:
Hard starting and poor initial running could be timing too.
Agreed Bob, had TB done and timing set correctly,before it was at 39-40 and now at 62-64 and cold start issues seem to have deminished.Still a little smokey.
 

whiterabbit7

Veteran Member
Joined
Feb 17, 2003
Location
Joplin,MO
TDI
2000 Golf GLS 201k miles
Once I have started the car in the morning, the following start-ups are fine. But again the air temp is higher now than when the problems first started. So I was thinking along the lines of GreenGeeker, that there could be an air leak, or a leaky injector.
 
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