Thermostat

[ssb1973]

I've been having an issue where the temperature on the dash on my Audi A4 tdi used to show 90 degrees Celcius when the car was warm, but since having a new clutch and DMF fitted the temperature goes to around 85 degrees, but doesn't increase, sometimes it drops to around 70 - 80 whilst driving on the motorway.

I've been to an Audi specialist to check it, and they couldn't see any problems on diagnostics, so don't think its the temperature sensor, they think it may be the thermostat. They quoted £113 to replace it, he said it would take 1 hour as he has to remove the alternator to reach the thermostat.

I phoned the Audi main dealers for a quote, and they said the part is £20.90, £2 for the housing, and it's a 3 hour job, with £119 per hour labour! Total cost is £427.03.

Is this job easy enough to do by a novice by purchasing the part and housing?

[mullardel34]

You haven't stated whether your A4 has the 1.8L turbo-engine or the 3.0L V6; the procedure is quite different...

Assuming that you have the 1.8L turbo-engine, here's a step-by-step write-up on thermostat replacement:

DIY: B6 A4 1.8T - Thermostat Replacement

As you can see, it's a fairly lengthy procedure (you have to remove the serpentine belt and the alternator, among other components), so be careful if you decide to attempt this repair as a DIY project. You're likely to lose a signifciant portion of the coolant during the repair procedure, so be certain to purchase the Audi-specific G12 coolant so that you can make-up any coolant loss.

Good luck!

[ssb1973]

Hi Mullardel,

Thanks for the response, the Audi's a 1.9 tdi. I've looked through the procedure, and I think I'll leave it to the experts.

Audi main dealer quoted £427
Independent Audi specialist quoted £113
non Audi Generic garage quote £40 labour + £22 parts.

Think I'll go for the generic garage, and buy genuine Audi thermostat and housing.

Thanks for the response.