MK5 Golf GTI

All Things Mk5 => Mk5 General Area => Topic started by: Dave_d on July 19, 2017, 11:43:10 am

Title: Which thermostat to replace?
Post by: Dave_d on July 19, 2017, 11:43:10 am
Hi guys, I believe I need my thermostat replacing on my 07 gti, I understand it has 3 with it being a dsg, does anyone know how to tell which one will need replacing? I drove to work this morning which is 11 miles at average of 30mph and it had only just reached around 75degrees
Title: Re: Which thermostat to replace?
Post by: Leco_GTI on July 19, 2017, 12:54:16 pm
Main thermostat. Once it's replaced, if it takes too long to reach temperature then you will need to replace the two inlines too. I am talking by experience  :happy2:
Title: Re: Which thermostat to replace?
Post by: lukemk5gti on July 19, 2017, 02:08:19 pm
A more detailed description as I've done all mine in stages to identify what causes what.

MAIN THERMOSTAT
The car never reaches temperature unless idling in traffic. Usually drops in temperature when coasting down a hill
Big job to replace this one circa £200 - £400

INLINE THERMOSTAT
The car takes ages to heat up. Often 30 solid minutes of motorway driving for me but once it does it stays at 90deg.
Easy to replace and a definite diy job. Right at the front of the engine with room to get hands in.

DSG
No experience as mine is manual but probably not a big deal.

My advice, check your symptoms again. Go for an hour long drive and see if it reaches 90 eventually. That means you can get away with the cheap inline fix.

If it doesn't reach 90 then unfortunately it's the main and quite possibly the inline too. Since the inline is only around £15 with negligible labour I would get both done together.
Title: Re: Which thermostat to replace?
Post by: Leco_GTI on July 20, 2017, 09:23:48 am
The symptoms described are spot on. A DSG has two inlines.
Title: Re: Which thermostat to replace?
Post by: Shoduchi on July 20, 2017, 01:17:14 pm
The symptoms described are spot on. A DSG has two inlines.

Depends on the year, 2008 have only 1 inline. :wink:

It has been explained in the forum before.
Title: Re: Which thermostat to replace?
Post by: Leco_GTI on July 20, 2017, 01:46:16 pm
The symptoms described are spot on. A DSG has two inlines.

Depends on the year, 2008 have only 1 inline. :wink:

It has been explained in the forum before.

Thanks for letting me know. I wasn't aware of that  :happy2:
Title: Re: Which thermostat to replace?
Post by: Dave_d on July 27, 2017, 12:26:04 pm
ID be more inclined to say the inline thermostat needs replacing, as it does eventually reach temperature. Once it's there it stays there. Just takes yonks to get there