Overheating ONLY at highway speeds
- Thread starter rcchris7
- Start date
nkgagne
Veteran Member
- Joined
- Sep 30, 2010
- Location
- Kitchener, Ontario Canada
- TDI
- 2015 Sportwagen 6M, 2006 Golf GLS TDI (sold)
Yes, but sometimes it's necessary to read things more than once! Glad we're on the same page. 
Morne
New member
Hi. Did you manage to find the cause? I am having the same issue on a different model Tdi
AndyBees
Top Post Dawg
- Joined
- May 27, 2003
- Location
- Southeast Kentucky
- TDI
- Silver 2003 Jetta TDI, Silver 2000 Jetta TDI (sold), '84 Vanagon with '02 ALH engine
This a very old Thread.
Yes, he did find the cause ......... bad head gasket. The info is on page two of this Thread.
To be clear, coolant circulation through the expansion tank is constant, regardless of T-stat function. Coolant leaves the head via a very small stainless steel pipe which has a small black hose connected to it that leads over to the expansion tank. From there coolant flows out the bottom of the expansion tank to the black metal pipe going into the back of the Water Pump housing (location of the T-stat). Also, coolant constantly circulates through the EGR and Heater systems and returns via the same black metal pipe to the WP housing (cast in the block). When that coolant gets hot it will open the T-stat, which is a gradual process... it just doesn't pop open fully.
Pressure in the system at full operating temp should range from about 7 psi to no more than 12 psi.
tat2
Well-known member
check your hoses if they are very soft and spongy change them. at highway speeds the pressure from the pump circulating the coolant can collapse your hoses but when your driving around the city not going as fast the coolant flows but its not enough pressure built up to collapse them. hope this helps.
I also have similar problem
Car overheated on the highway and there was no cabin heating.
Mechanic somehow ruled out thermostat water pump and heater core and decided to replace head gasket but the problem still persists
It is 2010 A3 1.6 TDI
Car overheated on the highway and there was no cabin heating.
Mechanic somehow ruled out thermostat water pump and heater core and decided to replace head gasket but the problem still persists
It is 2010 A3 1.6 TDI
johnsTDI
Veteran Member
changing a head gasket with-out checking basic things 1st is not a good mechanic if You ask me.? "he should of been more thorough on checking basics things 1st as follows..." would You not agree.?
- coolant Level & coloure ?
- Rad fan is it coming on ?
- change the thermostat ?
He claims he checked all of it
Not sure how but i asked for each part specifically and he had some explanation for each of them and sounded very confident about head gasket
Seems like im not the only one with this issue
Look at this post #7 in the linked thread specifically
http://www.vwaudiforum.co.uk/forum/...6-TDI-Overheating-issue?p=1089814#post1089814
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