TDI Overheating Issue

C

churchwalk

New member
Joined
Aug 18, 2016
Location
NorthEast
TDI
MK5 Golf 1.9 tdi pd 105
Hello!

Please can anyone advise what next to try to help my overheating golf?

Model:
- 1.9 tdi 2005 pd105 Engine code BKC

Symptoms - When accelerating hard for example from 50mph to 70mph the blowers will go cold, then the coolant temp gauge raises up, sometimes all the way triggering, then if will slowly drop down. \the temp then drops and the blowers go hot.
- Often when the car is stopped the fans are still going for it
- The coolant is sometimes spurts out of the heater tank overflow - due to over pressure?
- no fault codes

What I have tried:
- replaced header tank and cap
- replaced thermostat
- replaced radiator
- Coolant changed

Things I have checked:
- Coolant is flowing round, the top hose to the header tank gets hot. Therefore the pump is working.
- The oil looks normal, no mayo.
- As the fans are overrunning and the water gauge are both saying it is hot i don't think this is electrical.
 
cleaver

cleaver

Veteran Member
Joined
May 8, 2006
Location
Berwick, Nova Scotia
TDI
None - did own '01 and '02 Jetta TDI
churchwalk said:
Hello!

the blowers will go cold, then the coolant temp gauge raises up, sometimes all the way triggering, then if will slowly drop down. \the temp then drops and the blowers go hot.
Click to expand...

Sounds like a head gasket to me...Hook up VCDS and see if the actual engine temp is increasing/decreasing...??

Or. as my mechanic when I was young used to say, grab hold of the coolant pipe from the radiator and it is hot, but not hot enough to burn you then you are good. (Unless you have city boy hands and everything is too freaking hot...)
 
Last edited:
C

churchwalk

New member
Joined
Aug 18, 2016
Location
NorthEast
TDI
MK5 Golf 1.9 tdi pd 105
Have you checked the head gasket? Almost sounds like you are blowing combustion into the coolant
Click to expand...
There is no mayo in the oil and the coolant is mostly clean / pink. Is there anything I can do to check if the head gasket is gone?

WAG here. Could a soft/collapsing coolant hose be the cause?
Click to expand...
I think this could be issue, as the blowers drop out as the engine overheats, I just don't know how to check which hose? it only seems to do this at motorway speeds.

Water pump? The impeller may be partially failing at the shaft. The impeller may be slipping on the shaft under load.
Click to expand...
I am going to check this next. The return hose does get warm when the car is running so it think that is a sign it is working, though I will remove the thermostat and see that the impeller is in ok condition and cant spin freely.

Cheers for the advice, much appreciated.
 
C

churchwalk

New member
Joined
Aug 18, 2016
Location
NorthEast
TDI
MK5 Golf 1.9 tdi pd 105
cleaver said:
Or. as my mechanic when I was young used to say, grab hold of the coolant pipe from the radiator and it is hot, but not hot enough to burn you then you are good. (Unless you have city boy hands and everything is too freaking hot...)
Click to expand...
The top hose gets hot, I am sure this could burn me.

The bottom hose barely gets warm
 
S

stoner-tdi

Veteran Member
Joined
Nov 24, 2015
Location
cypress, TX
TDI
jetta sportwagen
churchwalk said:
There is no mayo in the oil and the coolant is mostly clean / pink. Is there anything I can do to check if the head gasket is gone?
Click to expand...
just because there is no coolant in the oil and no oil in the coolant doesn't mean anything...

your head gasket could be bad at an intersection of the cylinder and coolant passage. meaning when your motor goes to make a compression stroke it forces hot combustion gasses into the coolant system. if that is happening you are pumping air into your coolant system causing your coolant system to over pressurize forcing coolant out of your fill bottle. If you are experiencing bubbles in your fill bottle that is a good sign that the is an air source and there is no air source in a cooling system... you can go to the parts store and buy a coolant combustion tester which will test for combustion gas in the coolant..

https://www.google.com/search?q=coo...e=active&tbm=isch&q=coolant+combustion+tester
 
Hyde7278

Hyde7278

Veteran Member
Joined
Nov 11, 2012
Location
Central Mich
TDI
2001 Golf GL
Another way to test if the head gasket is allowing combustion gasses into the cooling system is to start the car (after sitting overnight) and let it idle of a minute or two and grab a hose and squeeze it if is hard to squeeze (pressurized) the head gasket is leaking causing the cooling system to pressurize.

Combustion testers are the best way to tell but the above test will give you a good idea that it is leaking and it's free.
 
T

tombom

New member
Joined
Sep 8, 2020
Location
Roodepoort johannesburg
TDI
Jetta 1.9 tdi
churchwalk said:
Hello!

Please can anyone advise what next to try to help my overheating golf?

Model:
- 1.9 tdi 2005 pd105 Engine code BKC

Symptoms - When accelerating hard for example from 50mph to 70mph the blowers will go cold, then the coolant temp gauge raises up, sometimes all the way triggering, then if will slowly drop down. \the temp then drops and the blowers go hot.
- Often when the car is stopped the fans are still going for it
- The coolant is sometimes spurts out of the heater tank overflow - due to over pressure?
- no fault codes

What I have tried:
- replaced header tank and cap
- replaced thermostat
- replaced radiator
- Coolant changed

Things I have checked:
- Coolant is flowing round, the top hose to the header tank gets hot. Therefore the pump is working.
- The oil looks normal, no mayo.
- As the fans are overrunning and the water gauge are both saying it is hot i don't think this is electrical.
Click to expand...
Hi Hi i am experiencing the same issue. If i may ask what was the problem and how was it fixed?
 
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