Intermittent temp gauge.

[Iceash]

Hi all,

had the stat changed as I was getting odd temp readings. As it climbed it would fall suddenly, then climb higher then fall again. It would eventually get to 90 then maybe now n then drop to say 70, hold then climb back to 90. The 49c would mirror this also on climate con. Could this be the cts? Or something else?

thanks,

Ash

 

[myth]

Definitely the CTS. If you have a vag com, surely it will throw a code.

 

[Iceash]

Definitely the CTS. If you have a vag com, surely it will throw a code.

Don't have access to vag com. Can't be anything else then?

Is it something Audi keep on the shelf?

 

[Bradderz_1988]

Mine did this a while back when i fitted a new temp sensor and thermostat !! I would be driving on motorway and it would drop to 70' then slowly creep back to 90' left it alone to see how it got on and its never done it since !! Both were genuine audi parts !!

 

[Iceash]

Been doing it for weeks now, new stat fitted today. Fitted the higher temp one though. Engine and oil nice n toasty.

 

[B5 BIKER]

Definitely the cts mate

 

[Iceash]

Audi likely to carry one on the shelf?

 

[B5 BIKER]

Ya they get changed that often they normally would
2 different versions though. 2 pin or 4 pin

 

[Iceash]

Ya they get changed that often they normally would
2 different versions though. 2 pin or 4 pin

Has 4 wires coming out of it so assume 4 pin. So other than feeding temp to dash gauge. What's its purpose?

 

[desertstorm]

Very common fault across almost all VAG cars 97-2005 ish.
GENUINE VW COOLANT TEMP SENSOR SENDER AUDI A2 A3 A4 A6 A8 TT S3 059919501A | eBay
Old design CTS will be black new design ones are green.

Closer to £30 from the dealers. They should have them is stock.

Karl.

 

[Iceash]

Funnily enough, I went through 3 in 5 years on my 6n polo!

 

[Bradderz_1988]

That one is the newer style 'D' shaped two pin sensor you need the old square style 4 pin one thats green they are what audi supplys and have superseded from the old blue square 4 pin sensor !!

But double check as some late TQS's have the 'D' shaped green one !!

 

[desertstorm]

They have 4 wires because there are two seperate temperature sensors in there. One supplies the ECU the other the dash for the temperature reading. One or both can be intermittent. Quite often you only notice because the temperature gauge starts going like a windscreen wiper.

 

[Iceash]

I had a D shaped one, changed surprise surprise. All works lol :-D

 

[B5 BIKER]

Good stuff, I had to change mine on my old A4, even my A6 now needed one also so it must be fairly common.
Both sides were shot, needle used to jump around and the ecu sensor also it used to make the engine run uneven and bring on the esp light

 

[Iceash]

Thankfully she behaved other than using a little more fuel. However when the one on the Polo failed it kept reving which was scary when trying to engine brake lol