⚠️ALL S3 8V OWNERS COOLANT LEAK!!!!!!

I've just had my thermostat and seals replaced on my 2014 S3 while it was in for a service and MOT, they noticed a bit of residue below the thermostat housing and recommended replacement so I've had it done before it gets worse.
The dealer also gave me a bottle of coolant in case it burps more air out the system over the next few miles, the S3 is notorious for air in the cooling system. Not under warranty so cost £670.
 
Great video by the way!

I drive a 66 plate A3 (2L Sportback) and I have a very similar issue, can see the leak itself in the engine bay (and a little bit dripping onto the roadway) but have yet to find the source.

Only major concern I have is whether it's covered by warranty, by reading the threads it would appear that it is covered.

I have an Audi technician coming out to the house tomorrow as repair is booked for 10 days time. Hopeful it is an easy fix.
 
I'm joining the club too, 2014 S3 with 46k miles. Took it in for suspected Haldex pump failure (slipped on ice plus VCDS gave error codes about it though it subsequently passed basic test) and ended up with thermostat replacement! Can't say I've noticed any smells, car was serviced a few months ago and not asked for more coolant since...
 
Just had mine recovered to Audi last Thursday due to ecu showing faults and not able to drive, RAC took car to Audi Friday!

Get video from Audi today. And a quote to fix the fault.

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Cars 63 plate with 61500 miles!
Think I’ll write a letter to Audi uk as causing ecu to fail is behind me in this day and age.
Surely should just shut down!

Getting car back Wednesday.


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I don’t have an S3 (A3 1.8 TFSI) but the coolant system and engine construction is more or less the same as the S3.

I had the coolant warning light on, engine got over 100 degrees and CEL/EPC light on constantly. Stopped it at once, got it towed in to the Audi dealer. Also had no heat in the car by the time it happened.

Turned out it was my thermostathousing, and waterpump that was faulty, including the wire loom/connector were corroded due to the leak. Trust me, they are a bitch to locate a leak on. 4-5 coolant hoses into the thermostat, it’s controlled by an actuator inside it and once it ***** up, your coolant system goes bananas.

And as for a DIY? Yes it’s possible, but it’s tight down there as it’s under the intake.. Best part? The whole unit is PLASTIC...

Thankfully, were spoiled with a 5 year/100000 km warranty in Norway, so got mine replaced, with new coolant, connectors and wires repaired at no cost even though the car was almost 5 years old.

So this does not only apply to S3 owners, but also A3 owners with the 1.8 TFSI (CJSA/CJSB engine codes)

Just as a heads up.

Cheers.
 
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Glad you got it sorted for free :)
I realised that my coolant was a bit low (middle of the marked section) so went and bought some G13 coolant from Skoda as I was passing by. Great service there (Citygate Watford), was offered a drink and seemed a much nicer place than Audi Watford! When I opened the cap some air came out and the level went up a bit so just needed around 2mm topping up.
Just a heads up to check the level shortly after the housing has been replaced, the guy at Skoda was telling me this happens on brand new cars too as the digital tool that fills up the coolant can create an airlock.
 
My car is being serviced today, not by Audi. The indy rang and told me that there was a problem with the coolant/water, I'm sure they said leak. £475 to fix.

My car warranty expires on Sunday at midnight with Audi but I seemed to remember hearing about this fault on the forum so thought I could get it covered under warranty, the garage said I could.

The warning light on the DIS hasn't come on though and I've had no obvious symptoms something is wrong, but from some quick reading that seems not to be too much of a surprise? I've booked in with Friday luckily on Friday so it will still be in warranty, but the Audi employee who booked me in also was questioning that the light wasn't on.

I need to get a better understanding of the issue when I collect my car later from the indy. Just a quick post for people to say if this sounds out of ordinary?
 
mike170 said:
Just had mine recovered to Audi last Thursday due to ecu showing faults and not able to drive, RAC took car to Audi Friday!

Get video from Audi today. And a quote to fix the fault.

Cars 63 plate with 61500 miles!
Think I’ll write a letter to Audi uk as causing ecu to fail is behind me in this day and age.
Surely should just shut down!

Getting car back Wednesday.

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Click to expand...

I would be quite polite but firm on both counts.
Leaking coolant seems relatively common and an ecu is a non-serviceable part that should be expected to last the lifetime of the car. Would be interesting to understand 'faulty' ECU as it maybe a reinstall/piggy back would work around it.
 
msdmjb said:
I would be quite polite but firm on both counts.
Leaking coolant seems relatively common and an ecu is a non-serviceable part that should be expected to last the lifetime of the car. Would be interesting to understand 'faulty' ECU as it maybe a reinstall/piggy back would work around it.
Click to expand...

Written to Audi executive and got reply back saying out of warranty. Not willing to offer good will payment. Waited 2 weeks for them to repair car, 5 days of which car sat awaiting response from Germany as to coding method!

Still not sure what caused ecu fault, but also needed new throttle body at £472.

Think I’ll be going down the warranty recall via dvsa


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To update my post above, yeah Audi confirmed the coolant leak (pic from Audi cam)
Upload 2019 4 5 20 45 58


Car is staying in over the weekend whilst they wait on parts to arrive and fixed on Monday, sadly no available courtesy car. So happened around 29k/3years. Coolant level was fine and no light on DIS.
 
@mike170 I had a similar experience when dealer was coding a new airbag control module, took around a week of backwards and forwards with Germany! Crazy stuff
 
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Had my water pump replaced on my 2015 S3 at 34K miles. Leaking from the thermostat housing. £540 from an Audi Specialist under a 3rd party warranty that was provided when I bought the car. Now have an Audi warranty. Threw a couple of warnings

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I've just joined this club too. 2016 S3 8V FL, 13,000 miles. Had the low level warning twice, a couple of weeks apart, so decided to investigate. I could see wet on the undertray, from above. I removed the undertray and found the tray wet with coolant. After drying everywhere off and restarting the engine, a drip started to appear from the plastic thermostat housing. It went into Audi main dealer today and they confirmed it was the thermostat housing leaking and replaced it under warranty. Very worrying that it is a common failure and can fail at low mileage. Has anyone found a part number for this and a how-to video for doing the job? I really don't want to pay what some have paid, to have this replaced.
 
craigs6124 said:
I've just joined this club too. 2016 S3 8V FL, 13,000 miles. Had the low level warning twice, a couple of weeks apart, so decided to investigate. I could see wet on the undertray, from above. I removed the undertray and found the tray wet with coolant. After drying everywhere off and restarting the engine, a drip started to appear from the plastic thermostat housing. It went into Audi main dealer today and they confirmed it was the thermostat housing leaking and replaced it under warranty. Very worrying that it is a common failure and can fail at low mileage. Has anyone found a part number for this and a how-to video for doing the job? I really don't want to pay what some have paid, to have this replaced.
Click to expand...

Just out of curiosity, do you drive with Start / Stop enabled or disabled?
 
The more I read this forum and see these posts, the more nervous I get. It seems from recent posts that Audi still are no prepared to accept a design fault and good will gestures are a lottery. My 2015 S3 with 29k miles is now well out of warranty - does anyone recommend a 3rd party warranty company that would cover this eventuality at a sensible price?
 
You could just get the part looked at by an Audi specialist and have it replaced.
 
So my pump or whatever was changed a few weeks ago after coolant leak. Car is now out of warranty, I just had a call from my dealership and seems like Audi UK have asked them to do a software update (or something ) to check the temperatures or whatever and make sure its all working fine.. this seemed odd....

I mentioned that "car has been modified" I didn't say tuned but he said "thats ok, we aren't touching the engine control unit". Anyone had something similar....? They are giving me a courtesy car for the day so thats fine, I just thought it was a bit strange.
 
So they randomly called you up and said that they want to take the car back in? Strange indeed
 
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HertS3 said:
So they randomly called you up and said that they want to take the car back in? Strange indeed
Click to expand...
Yeah.... Maybe it's not that strange but I haven't seen anyone else mention something similar.. As long as they don't touch the ecu or tcu I'm fine with it though really...Still curious as to what exactly they are doing and why
 
Interesting that Audi are potentially taking an interest, albeit 3 years after people reported it.

I had this on my 1.8 (also EA888 Gen 3) and rarely used start-stop.

Curiously my S3 regularly has the fan running on after engine switch off but I think I only had that once on the 1.8. Admittedly we are talking different power output and heatsoak between these two engines.


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jm-darcy said:
The more I read this forum and see these posts, the more nervous I get. It seems from recent posts that Audi still are no prepared to accept a design fault and good will gestures are a lottery. My 2015 S3 with 29k miles is now well out of warranty - does anyone recommend a 3rd party warranty company that would cover this eventuality at a sensible price?
Click to expand...
Just had mine done after a month of ownership through Evans Halshaw mechanical breakdown warranty. 2015 s3 with 27k on the clock. Cost £670 to fix
 
Just dropped my car off at Audi for suspected coolant leak as the level is dropping, the tech advised that they do need topping up from time to time due to temperature changes. Anyone else think this is BS? All the cars I've owned so far haven't needed their coolant topping up...even the Cayenne I had when I was living in Abu Dhabi with desert heat didn't need topping up!
 
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I've never heard of temperature changes causing coolant to go down.

I think the issue is that the S3 engine doesn't have coolant bleeders on it, so there is no way to fill it properly, unless you use a vacuum pump and then fill it under vacuum. The result is that this engine is notorious for air bubbles, which will eventually work their way out, causing the coolant level to drop.

Of course, there is also the thermostat leakage issue.

Anyway, I've had mine remapped, and as part of the tune, the thermostat has been remapped, so the engine runs cooler and should generate less pressure in the coolant system, so with a bit of luck, there should be less stress on the thermostat housing and it won't crack again.
 
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ZipZap01 said:
I've never heard of temperature changes causing coolant to go down.

I think the issue is that the S3 engine doesn't have coolant bleeders on it, so there is no way to fill it properly, unless you use a vacuum pump and then fill it under vacuum. The result is that this engine is notorious for air bubbles, which will eventually work their way out, causing the coolant level to drop.

Of course, there is also the thermostat leakage issue.

Anyway, I've had mine remapped, and as part of the tune, the thermostat has been remapped, so the engine runs cooler and should generate less pressure in the coolant system, so with a bit of luck, there should be less stress on the thermostat housing and it won't crack again.
Click to expand...

Who mapped your car ? Never heard of a thermostat been mapped ?
 
Hi all,just been reading the above comments,well had my car just over 6months now and been complaining about the smell of antifreeze,been audi 3 times and they said nothing wrong,had coolant valve and air valve changed at the price of £1400 as they said that’s what was wrong got that paid by the garage I bought it from as had a warranty for 6 month,got car back and I still had the same smell,took it back to Audi and they said it was the antifreeze what had spilt on my engine and it needed cleaned,so I had it washed off and guess what?still same smell only this time I could see water,so off back to Audi who have just told me it now needs the thermostat housing replaced at £945,I have hit the roof as it’s just out of warranty now,they said well it wasn’t there before to which I’ve replied it must of been as it smelled of antifreeze still,been intouch with Audi uk and now waiting of a reply,I’ll keep you all updated on what’s said.oh and worse of all it's in for dsg oil and diff oil so got another £345 on top of that this car is costing a fortune only just fitted 4 tyres and middle box delete
 
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audi upgrades
Sag said:
Hi all,just been reading the above comments,well had my car just over 6months now and been complaining about the smell of antifreeze,been audi 3 times and they said nothing wrong,had coolant valve and air valve changed at the price of £1400 as they said that’s what was wrong got that paid by the garage I bought it from as had a warranty for 6 month,got car back and I still had the same smell,took it back to Audi and they said it was the antifreeze what had spilt on my engine and it needed cleaned,so I had it washed off and guess what?still same smell only this time I could see water,so off back to Audi who have just told me it now needs the thermostat housing replaced at £945,I have hit the roof as it’s just out of warranty now,they said well it wasn’t there before to which I’ve replied it must of been as it smelled of antifreeze still,been intouch with Audi uk and now waiting of a reply,I’ll keep you all updated on what’s said.oh and worse of all it's in for dsg oil and diff oil so got another £345 on top of that this car is costing a fortune only just fitted 4 tyres and middle box delete
Click to expand...

You won’t get any help from customer service, waste of space!

Wouldn’t get them to change rear diff oil as they don’t clean filter. Do a search the motor needs removing and clean filter.




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mike170 said:
You won’t get any help from customer service, waste of space!

Wouldn’t get them to change rear diff oil as they don’t clean filter. Do a search the motor needs removing and clean filter.




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Audi customer service calling huddersfield Audi at 12 today to get it discounted I’ll let you know the outcome,I will be asking them over the filter thanks for that
 
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Sag said:
Audi customer service calling huddersfield Audi at 12 today to get it discounted I’ll let you know the outcome,I will be asking them over the filter thanks for that
Click to expand...
Well as you said Audi uk a waste of time,just been on phone to them and all they can say is Audi huddersfield arnt willing to help and said car was fine when checked,they say this is not a common problem with theses cars lol,I said it’s amazing how so many have the same fault on here,they said we can’t comment on what goes on forums,what a waste of space eh!!!
 
Well just seen mine is leaking at the pump so booked into Audi for a look.
 
What is at front of engine under inlet manifold please?
Well just got car back yesterday as had water at front of engine,to which Audi said was from the thermostat housing at the back and run to front of engine,to which I said I find hard to believe as water would run to the back,well as you can see above £945 later ment to be fixed,just been out in car done 50 mile and guess what?water leaking at front of engine stillto say I’m ****** off is an under statement wait till I get there on Monday was ment to be going off today as booked a lodge for weekend so also lost £300 there aswell wife not happy at all.
 
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Sag said:
What is at front of engine under inlet manifold please?
Well just got car back yesterday as had water at front of engine,to which Audi said was from the thermostat housing at the back and run to front of engine,to which I said I find hard to believe as water would run to the back,well as you can see above £945 later ment to be fixed,just been out in car done 50 mile and guess what?water leaking at front of engine stillto say I’m ****** off is an under statement wait till I get there on Monday was ment to be going off today as booked a lodge for weekend so also lost £300 there aswell wife not happy at all.
Click to expand...

Water pump and thermostat all one unit,
Located under inlet manifold.

Quoted 3 hr job from Audi to replace!




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mike170 said:
Water pump and thermostat all one unit,
Located under inlet manifold.

Quoted 3 hr job from Audi to replace!




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Click to expand...
Thanks for reply,Had the thermostat housing changed and still leaking then as water coming out near inlet manifold
 
Sag said:
Thanks for reply,Had the thermostat housing changed and still leaking then as water coming out near inlet manifold
Click to expand...

How long ago you have thermostat changed?
Could be an related issue is you only option?


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