Overheating car - tried everything

**AZA** · 11-10-2009,03:00 PM

After having the waterpump in my car replaced, along with the radiator temp sensor, thermostate with housing and "both temp sensors" and the fan relay control unit, my car is STILL overheating.

Is there anything else left to replace? When the dashboard water gauge is on just over 110, code 51 on the climate control shows 66 degrees. When I then set code 49 on the climate control, it says 82 degrees. This corroborates what the garage said, that there's a difference of 30 degrees roughly.

The fans don't come on, and when I do get them on using AC blasting out, the temperature didn't seem to stop rising on the dash when I rev the car a little.

Here's a pic of what looks like it's been replaced, I've heard the temperature sender is a relatively common fault, but it looks like it's been replaced? Do you think from the pic the sender has been replaced?

Could anyone please give me any advice as I don't want to take it to Audi for about £500 if I can do it myself. This is driving me mad. I'd really really appreciate any advice that can help me get to the bottom of this.

**T.sport** · 11-10-2009,03:38 PM

Is there definately not an air lock,and no blockages in the radiator?And have you put the car on vagcom?

**AZA** · 11-10-2009,09:37 PM

Well the bottom radiator hose is coolish, and can be squeezed, whilst the top one is warm (Can't remember if it can also be squeezed). I heard it should be pressurised. How can I tell it is an airlock, and remove it if this is the case?

Thanks

**AZA** · 14-10-2009,10:45 PM

I've now learnt it's not an airlock, as the garage bled the system and tried to remove any airlocks.

The garage in fact did both the sender and thermostat when they did the waterpump too. The problem now seems to be that the fans don't come on when the dash gauge gets over 90. The thing I don't get is that the fans work when I turn the AC on, but it still doesn't cool the engine down at all.

Is there some sort of controller to make the waterpump go faster that could be faulty, or some sort of switch that triggers the fans when the car engine gets hot? Can anyone offer any other suggestions? This is driving me insane.

Thanks very much

**T.sport** · 14-10-2009,11:17 PM

Hold on,looking at your photo's,what engine is that?

**GillCee** · 15-10-2009,09:43 AM

Hi. Had the same problem with my A3, particularly when travelling in slow moving traffic. Garage said that it was a fuse on top of the battery which had burned out and was causing overheating. Only cost a few cents to change and everything is fine now. Might be worth checking.

**AZA** · 15-10-2009,02:33 PM

I'm not sure what engine code it is, but it's the 1.6 petrol.

I'll have to have a look at the fuse under the battery cover, hopefully it's that. Did the AC work even though the fuse was blown though?

Thanks all for your help, it's much appriciated.

**T.sport** · 15-10-2009,03:01 PM

[QUOTE=AZA;423442]the radiator temp sensor
What do you mean by this part?

**GillCee** · 15-10-2009,03:50 PM

Not sure about engine code either - mine is 1.8T and yes the AC worked fine. Good luck.

**AZA** · 15-10-2009,09:56 PM

[QUOTE=T.sport;425350]

Originally Posted by AZA

the radiator temp sensor
What do you mean by this part?

Sorry I meant the temperature sender and the thermostat.

Hopefully it is just a simple fuse, is it just a standard sized one? The Haynes manual says it's a 30amp, but I wondered if they'd be larger if they're in the engine bay.

Thanks