MK5 Golf GTI coolant temp

Moanin

Can anybody shed some light on this please? I'm not sure whether its thermostat or coolant Temp sensors:

2008 DSG Golf GTI, the coolant temp needle will sit at 90 when moving in traffic but when driving on motorway 100kph plus it will drop to 70ish and back to 90 and keep droping and jumping between the 2 on an off.

Thanks

Moanin

Moanin wrote: »

Can anybody shed some light on this please? I'm not sure whether its thermostat or coolant Temp sensors:

2008 DSG Golf GTI, the coolant temp needle will sit at 90 when moving in traffic but when driving on motorway 100kph plus it will drop to 70ish and back to 90 and keep droping and jumping between the 2 on an off.

Thanks

I have the exact car and had that exact problem.
It was the thermostat .

While getting it changed get the intake manifold cleaned as it will be full of ****e.

Moanin

Thanks was yours DSG? Did it cost much to replace?

Moanin

Moanin wrote: »

Thanks was yours DSG? Did it cost much to replace?

It is a DSG not that it makes a difference .
It wasn't cheap unfortunately ,
Havent the exact figure but it was between 400/500e all in.
Apparently a very labor intensive job

Moanin

BrownFinger wrote: »

It is a DSG not that it makes a difference .
It wasn't cheap unfortunately ,
Havent the exact figure but it was between 400/500e all in.
Apparently a very labor intensive job

Jaysus that's pricey!

ondafly

had the exact same symptoms on a mk7 gti dsg - thermostat replaced under warranty though.

Moanin

Moanin wrote: »

Jaysus that's pricey!

yep,
Just looked back through my mails.
VW Naas quoted me 310 inc vat .
So the extra must have been the manifold cleaning .

Moanin

BrownFinger wrote: »

yep,
Just looked back through my mails.
VW Naas quoted me 310 inc vat .
So the extra must have been the manifold cleaning .

Sound. Thanks for that.

George Dalton

The main thermostat replacement is labour intensive because the intake manifold has to be removed to access the thermostat. It makes sense to do the intake port cleaning at the same time as there is a labour saving by doing both jobs together. Expect to pay about €360 for both jobs if done together.

However the DSG cars have a second thermostat for the gearbox oil cooler which is very cheap and easy to change. So what you could do is get that replaced first and see if it fixes the problem.

Moanin

George Dalton wrote: »

The main thermostat replacement is labour intensive because the intake manifold has to be removed to access the thermostat. It makes sense to do the intake port cleaning at the same time as there is a labour saving by doing both jobs together. Expect to pay about €360 for both jobs if done together.

However the DSG cars have a second thermostat for the gearbox oil cooler which is very cheap and easy to change. So what you could do is get that replaced first and see if it fixes the problem.

Thanks George!

Moanin

Following up on this. I don't do much motorway driving - Round trip to work 20 mins- max speed 80kph, but I drove on motorway for approx. 60 kms last weekend and the needle sat on 90 the whole way once engine warmed up. On the return journey which was around 4 hours later back on the motorway once more the needle was acting up once more. Strange one.....