VW diesel thermostat / temp control
Discussion
My work horse car is a '11 Passat 2.0l diesel which has sometimes takes up to 40mins plus to heat up on the m/way and other times will be fully up to temp in 10mins... initially I thought it was a thermostat (I have been told this is a bit of a pain to change and includes removal of the alternator), but for the next week it behaves it self! A couple of weeks later, I get the same problem again for a day or so before it reverts to normal.
The question I have is this just a normal VW diesel engine issue and I should I just change the thermostat or is it some other electrical issue and I will need to get my local VW specialist to find the problem / fix it?
I dont want to leave it like this as I expect it will cause damage to the engineering running cold...
Thanks in advance Alex
The question I have is this just a normal VW diesel engine issue and I should I just change the thermostat or is it some other electrical issue and I will need to get my local VW specialist to find the problem / fix it?
I dont want to leave it like this as I expect it will cause damage to the engineering running cold...
Thanks in advance Alex
Edited by Alexxtreme on Thursday 28th July 22:40
Hi xjay1337, thanks for your comments.... my car is a 11 reg. Is it the same car with the emission VW recall?
Right - had my local garage change the stat - it came as a complete unit including the housing (he said) for around £25. Changing was a right pain for him which including removing the alternator and removing the aircon pipes (needed a re-charge afterwards). £370 in incl the service
So the drive this am was 16 miles with gentle start then 10 miles on the m/way followed by a couple miles and the temp never went above 75C... it even dropped on a down hill section.
I am sure I did not notice this before the same garage changed the timing belt together with the water pump and tensioner. Any other ideas???
Right - had my local garage change the stat - it came as a complete unit including the housing (he said) for around £25. Changing was a right pain for him which including removing the alternator and removing the aircon pipes (needed a re-charge afterwards). £370 in incl the service
So the drive this am was 16 miles with gentle start then 10 miles on the m/way followed by a couple miles and the temp never went above 75C... it even dropped on a down hill section.
I am sure I did not notice this before the same garage changed the timing belt together with the water pump and tensioner. Any other ideas???
Brilliant R E S T E C P :-),
I was about to post to say that I have changed the main thermo with still not luck and the problem it seems random. Sometimes it heats up and others it does not. No one I talked to knew of a second thermostat and I had a similar problem on an older BMW 520 where the second thermostat was faulty...
anyway I have brought the stat and will give it a go... the better mpg would be great and it can not do the g/box any good running colder that it should I guess.
Cheers Alex
I was about to post to say that I have changed the main thermo with still not luck and the problem it seems random. Sometimes it heats up and others it does not. No one I talked to knew of a second thermostat and I had a similar problem on an older BMW 520 where the second thermostat was faulty...
anyway I have brought the stat and will give it a go... the better mpg would be great and it can not do the g/box any good running colder that it should I guess.
Cheers Alex
job done - took around 30mins though this was as I had not taken off the air box before plus fiddling around with those bloody clips! Next time I am car shopping I will probably get some hose clip pliers https://www.amazon.co.uk/Sealey-VS166-Clamp-Pliers...
Yes - job done and first test today and fully warmed up in 8 to 10 mins where as before it was +20mins! Oil temp also came up to temp much earlier as well which has to be good for the engine. Thanks again :-)
One think I am concerned with was a possible cooling air lock. I lost around 0.25 - 0.5ltr - not enough to show on the floor as it was caught by the tray under the engine and since then there has been no sign of any change in the header tank fluid levels. Is there anyway of venting off any air in the system?
One think I am concerned with was a possible cooling air lock. I lost around 0.25 - 0.5ltr - not enough to show on the floor as it was caught by the tray under the engine and since then there has been no sign of any change in the header tank fluid levels. Is there anyway of venting off any air in the system?
Gassing Station | Engines & Drivetrain | Top of Page | What's New | My Stuff