STILL overheating - PLEASE help! - Pics included

TDIQ

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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.



 
that sounds like a nightmare.

Only other thing could be a blockage somewhere. With the engine and coolant cold, take off the coolant tank cap and start the engine. Then check to see if you can see coolant being returned to the expansion tank from the small top hose.

Final thing could be an airlock?
 
It's not blocked, I can see water flowing around into the coolant. How can I remove an airlock? Is there a valve somewhere I can release air with? I've tried by revving it with the cap off but it still makes no difference.

Any other ideas?
Thanks
 
have a search on here for "airlock" there's a few pieces of advice and help and loads of tests to try.
 
If you put the heaters on do you get warm air or cold?
 
I only tried to see if I could get cold, but I'm sure I can also get hot aswell.

I noticed my oil breather pipe has a split in it, and when I had a look I split it completely, if that makes any difference.

The only other thing that may be of interest is the bottom radiator pipe isn't really hard when the car is running. I can squeeze it and it pumps more into the coolant tank. Does that mean anything either?

Thanks
 
After thinking for a little while about this, I wondered if it was even possible for the car to be getting to 110 degrees on the dash, if the car was just being revved to say 3.5k, for about 3 minutes unless the coolant system was completely ruined. As there's water clearly flowing around into the coolant tank (Not gushing, but an OK rate I presume), perhaps it's simply a faulty gauge on the dash? Especially with code 49 saying 82 degrees and 51 saying 66.

Could it be just the dash gauge? And is the warning light that comes on when the car overheating going by the dash value or the other sensor values? Because if it is the dash I could just leave it perhaps?

Thanks
 
The only other thing that may be of interest is the bottom radiator pipe isn't really hard when the car is running. I can squeeze it and it pumps more into the coolant tank. Does that mean anything either? Thanks

I have the exact same problem on mine, after having the Radiator, Water Pump (which was broken) and thermostat replaced.

The difference on mine is that the 49c reading on the CC unit matches my dash gauge, so it sounds like your temp sensor could be out. Try taking it out and cleaning it - literally a 30 second job. If no joy, you may as well buy one from your local parts dealer - they don't cost that much.

To add, have you noticed if your radiator is hot after a drive? Although my temps get up to 105c, I can still touch the Rad - it's not cold, but it certainly isn't warm.

I'm thinking it could be that my Thermostat was replaced with faulty one - that it's stuck shut and not allowing coolant to the rad. That would explain (to me) why the bottom pipe is not pressurised and the rad is only luke warm to the touch. I'm not too sure if i'm correct though.
 
Thanks for the reply. Is the temp sensor different to the thermostat? Where can I find the temperature sensor and how do I go about cleaning it?

Thanks again, as hopefully this could solve my problem.
 
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 or can anyone offer any other suggestions? This is driving me insane.

Thanks