Thermostat or Temp Sensor

Chrismawa

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My A4 1.9TDI 130 doesn't get to 90 on the temperature display. After reading around on here it seems it will be either the thermostat or temperature sender. Is there any way to tell which? Or just a case or trial and error?
 
If the stat has failed stuck open then you should notice that the engine is slow to warm up and the heater doesn't work well.The CTS is more for smooth running
 
Change the stat first its £10 and is the easier of the 2 to replace. Drain the coolant or top up as youl loose some in the process
 
If it is the stat and it's stuck open the car will very slowly get upto 90 if at a standstill and keeping the revs to about 2k. I had this but once I took the stat out discovered that a location lug had broken off the stat elbow and got stuck not allowing it to close, but this is a rare occasion.

If there is no change to the temp after doing the above then the sensor is the next culprit.
 
When my stat was on its way out the temp would go up to 90 if I was pushing the engine a bit as soon as took some stress of the engine ie going downhill then the temp needle would drop almost to the bottom. Also it seemed to take ages to heat up in the winter.
 
Is there any preferance on make of stat?

ECP are selling Circoli ones for 3 quid odd at the moment.

Should I replace the housing at the same time?
 
im a fan of buying genuine vw/audi thermostat's as i find the cheep ones fail more regularly might cost a tad bit more but should last longer
 
Don't buy ECP.Put one in an S3 last year and it only lasted a few weeks
 
Genuine it is then.

How much G12 will i need to refill the system?
 
think i have found out? allow for 5l...

worth using gen g12 or get some antifreeze with g12 spec?
 
It's g13 now from vw lol I buy genuine stuff last time but I bagged 2 bottles of eBay for price of one he he
 
Want to do it this weekend really and looking now I'm not paying out for genuine antifreeze. ECP finest will do I reckon.
 
Cheers, I thought people must use other than Audi own as thats rediculous price.

Off to Audi in a bit for the stat and oring then ECP for some antifreeze think they do Triple QX stuff.
 
Unless you going to flush the system it not recommended to mix the vag anti freeze, as there will still be loads left in the engine & heater matrix. You also don't need 5 litres I use a 50/50 mix of G13 & water but you could go lower, you will only need at most 2 bottles of G13 for the job you are doing, it's not worth mixing it with other brands.
 
After all that I ended up getting a part from my local motor factors as my 3 local audis didn't have 1 in stock!

Unfortunately I missed your message B5NUT and have bought some antifreeze for the job. I guess I'll give the system a flush then.

Should have it all sorted tomorrow.
 
Don't buy ECP.Put one in an S3 last year and it only lasted a few weeks


I replaced mine in my 52 A4 1.9 tdi 130 with the ECP one 2-3 weeks ago and I'm sure it's gone again, unless I have an air lock...? I think I may replace it with a genuine one before I do the temp sensor but not sure on the price from the dealers~?
 
i replaced both parts last year with gen and been fine all year then this morning,first frosty morning and it took a fair while to get to 90.
must have been in stop start traffic for a good 25 mins and was still at 70 but im just putting it down to these 1.9 engines just dont get very hot and struggle to get up to temp in cold conditions!
 
I replaced mine in my 52 A4 1.9 tdi 130 with the ECP one 2-3 weeks ago and I'm sure it's gone again, unless I have an air lock...? I think I may replace it with a genuine one before I do the temp sensor but not sure on the price from the dealers~?

Audi quoted me 17 quid i think it was the other day. But surely you would change the temp sensor before changing the stat again. I changed both on mine.
 
Audi quoted me 17 quid i think it was the other day. But surely you would change the temp sensor before changing the stat again. I changed both on mine.


I would but the stat is sooo easy to do do whereas the temp sensor seems impossible to get to and I have asked the question on the forum regarding the difference between green and black as I have a black one on the car but ecp supplied me a green one. They also do not do new o rings and clips so I dont know what to do.
 
Just remove the top boost pipe then you can get to it fairly easily.

ECP do seem to of stopped doing the clips and rings, I bought a temp sender with clip and oring off them in January but when I bought the other day they said they had none, thankfully I had a spare clip and I have a box of orings.

I had a green one come out and green back in. Your not looking at the fuel temp sensor are you?
 
Just remove the top boost pipe then you can get to it fairly easily.

ECP do seem to of stopped doing the clips and rings, I bought a temp sender with clip and oring off them in January but when I bought the other day they said they had none, thankfully I had a spare clip and I have a box of orings.

I had a green one come out and green back in. Your not looking at the fuel temp sensor are you?

I dont think so ? I'm taking off the plastic engine cover and looking over the back of the engine down the left side, it looks to be right? It is sitting at an angle slightly upside down?
 

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