1.9tdi thermostat replacement

[Adman]

Since I've had my car the temp gauge has never got above 70 deg. I changed the CTS hoping that was the problem but to no avail. Pretty sure its the thermostat after reading this...

Thermostat, water pump or sender unit

I'm gonna have a go myself, just wanted to confirm location of thermostat on a 1.9tdi 130? I presume its take the radiator hose off to drain? Also how much coolant should i expect to replace and at what ratio.. 50%?

I normally use genuine parts no matter what but would a cheapy ebay one do the trick? trying to save money as skint at the mo.

Thanks in advance

Ad

[Doctle Odd]

Thermostat isn't expensive mate. There's a drainage tap at the bottom of the radiator you can drain a lot of the coolant there and most of the remainder at the oil cooler. There's 2 hex bolts holds the thermostat cover in place take them out, you can leave the hose on if you wish and move the cover away from the engine. Take out the old thermostat (note which way it goes) and put in the new one and the new seal, don't over tighten the bolts. Make sure all pipes are on properly and the drainage tap is closed then add coolant (G12) don't dilute it. Coolant should be changed every few years anyway. Take you less than an hour

[Col]

Just to add, the thermostat is locked into the plastic flange section.

To remove it twist then gently pull. It is easy to break the plastic retaining tabs in the flange housing.

The flange is tucked up behind the alternator and the two bolts are either 5mm allen (hex) or 10mm normal bolts heads so either should fit. You do not need to remove the alternator.

[Adman]

Thanks guys, much appreciated. Does genuine or not make much difference?

[pdlh]

Sorry to high jack the thread, I'm also experiencing the temperature gauge not going above 70 degrees on a 1.9tdi, I've had the car 8 years and I'm sure it used to go to 90 degrees on most good runs, but now I only see 70 degrees, I'd put it down to the cold outside temperature and having the heating on 26 degrees, but seeing this post, it's now got me thinking, could the engine not running at it's normal 90 degrees, also reduce fuel economy? I'm struggling to return the MPG I used to get?

Paul

[Doctle Odd]

Yes if the ecu thinks the car is at a lower temperature it will use a different map with different settings and parameters so it will effect fuel economy

[Adman]

Sorry to high jack the thread, I'm also experiencing the temperature gauge not going above 70 degrees on a 1.9tdi, I've had the car 8 years and I'm sure it used to go to 90 degrees on most good runs, but now I only see 70 degrees, I'd put it down to the cold outside temperature and having the heating on 26 degrees, but seeing this post, it's now got me thinking, could the engine not running at it's normal 90 degrees, also reduce fuel economy? I'm struggling to return the MPG I used to get?

Paul

Fuel economy will be downs the car is constantly over fuelling to get up to temperature. it should get up to 90 and sit there in all but extreme cold temperatures

[Col]

It is good practice, whilst the system is drained down to replace BOTH the temp sender and the thermostat, as they BOTH fail.

Saves you buying antifreeze twice.

[Alfonzo]

Guys, is there a 'diagnostic procedure' for determining whether its the temp sender or thermostat (or both) that's failed? E.g. Using VCDS?

[Doctle Odd]

VCDS scan will tell you if the CTS has a fault