Cooling fans go wild.

[Graeme4130]

I had something similar on mine. One of the cylinder head thermostats were faulty, and the engine light came on
It ran what I think was the oil cooling fan all the time, so my car sounded like a passenger jet about to take off
Was fixed under warranty

[davis1888]

The power of the forums, had an issue tonight and remember reading this post last month...

Drove about 20 miles this evening and as I pulled up at a junction there was an awful lot of noise coming from the fans, drowning out the noise of the engine. Fans running full blast with engine on and for about 5 mins after engine turned off at a lower fan speed. Started the car to drive back and it kicked back in immediately, fans on full blast.

Engine temp sat between 52 degrees and 57 degrees on way home, would always expect a little higher when giving it a push along with the right foot. Water temp raised 1 notch above the 90 degrees as reported by another user. Lifted the bonnet and engine was reasonably cold when compared with the heat I’ve felt off it before after a 40 mile run out.

Figure this might be a faulty thermostat as suffered by one of the German users on here. Car still under warranty, so will be dropping it into the stealership to get sorted.

[davis1888]

Car has been in the workshop for 2 days to get this fixed, they called today (day 3) to say I could take it back and then phoned again shortly after to say that the Master Technician (who I'm told is quite anal about his work ) wanted to check it all over again today to make sure everything was working as planned.

Not sure how invasive the work is to replace the thermostat, i.e. where is it located in the engine / engine bay as one of the previous comments mentioned having to take a the front bumper off, etc to get into it + another comment mentioned a cylinder head thermostat which sounds like a more invasive piece of work.

Always worry when you start opening cars up like that, especially one loaded with technical options, camera's, sensors, etc that there is always some sort of knock on impact and niggly faults after. Very much looking forward to getting it back as the 19 plate 1.4 TFSI 150PS Manual A4 Saloon they gave me is not really cutting it Though oddly as it's in Nardo Grey all my neighbours have been asking if I've got a new car, never said a thing about the RS when I got it

[Gio G]

I also have this issue on my RS5 on Saturday, seems to be a bit of a theme... My cooling fan is going crazy from cold start up. However I yet to have an engine check light come on. However the start/stop disabled itself, but now working. Not really used the car since. Would I be safe to drive to dealer within 15 miles?

G

[PieterZ]

No problem, just don’t floor it as the oil doesn’t heat enough.
I drove mine more than 100 km with blazing fans.

[Gio G]

So mine is now in the dealer, as the part was on back order. I never got an engine check light and the fan issue just went away, as soon as I took it into the dealer first time, which is typical.... They said I could drive it with no problems until part arrived.. Did a drive to Wales, some 500 mile return trip and no problems, then suddenly day before scheduled work, engine light comes on and fan starts going crazy again.. They said it was a fault with the map controlled thermostat.. nearly £1,000 to replace + labour, thank goodness for warranty!

Gave me an A5 40 TFSI as a courtesy car, my word it's slow

[PieterZ]

I never got to now the amount, that is steep for a thermostat!
Hopefully that isn’t due any more after warranty.

[bing0r]

My RS4 has also gone in today with what sounds like a broken thermostat issue as others have posted on here. Fan's going crazy on startup, resulting in oil not coming up to temp. Also got a check engine light on and warning that start / stop is not working. Also coolant temps are also one notch above 90 where it normally is at temps.

To top it off, got a flat tyre which needs replacing too.

[PieterZ]

The power of the forums, had an issue tonight and remember reading this post last month...

Drove about 20 miles this evening and as I pulled up at a junction there was an awful lot of noise coming from the fans, drowning out the noise of the engine. Fans running full blast with engine on and for about 5 mins after engine turned off at a lower fan speed. Started the car to drive back and it kicked back in immediately, fans on full blast.

Engine temp sat between 52 degrees and 57 degrees on way home, would always expect a little higher when giving it a push along with the right foot. Water temp raised 1 notch above the 90 degrees as reported by another user. Lifted the bonnet and engine was reasonably cold when compared with the heat I’ve felt off it before after a 40 mile run out.

Figure this might be a faulty thermostat as suffered by one of the German users on here. Car still under warranty, so will be dropping it into the stealership to get sorted.

Exactly what I had. I’m Belgian btw.

[J88NOG]

Morning All,

Just a note to say that my car has just had a faulty map-controlled thermostat replaced under warranty @ approx. 16k miles.

We had the 'jet taking off' fan symptoms and arranged to get the car looked at (though no engine light). Once in the workshop the issue was confirmed and replaced pretty quickly.

This looks like a pretty common fault, and I'd assume this has been a manufacturing defect with a batch of the thermostats. I wonder how many RS4's have been affected, as there are quite a few on here already.

J

[s4tokyo]

Morning All,

Just a note to say that my car has just had a faulty map-controlled thermostat replaced under warranty @ approx. 16k miles.

We had the 'jet taking off' fan symptoms and arranged to get the car looked at (though no engine light). Once in the workshop the issue was confirmed and replaced pretty quickly.

This looks like a pretty common fault, and I'd assume this has been a manufacturing defect with a batch of the thermostats. I wonder how many RS4's have been affected, as there are quite a few on here already.

J

I had this issue twice on my B8 S4 and once on my B8 RS4. It's an unresolved problem, given the amount of respective forum posts - at least too common for a premium mid segment car. You'd expect that Audi would have sorted this first time around - revised Design or new Supplier:(

[Johnnie5]

Just had the same thing last week.

Fans went wild. Kept firing up again everytime I started the car. Start stop was disabled and CEL light in amber came on.

I gently took car home. Although it felt and operated normally (except sounding like a jet).

Audi assistance diagnosed the faulty Thermostat next day and it's being replaced as we speak.

J

[Crawfc]

My RS4 has also gone in today with what sounds like a broken thermostat issue as others have posted on here. Fan's going crazy on startup, resulting in oil not coming up to temp. Also got a check engine light on and warning that start / stop is not working. Also coolant temps are also one notch above 90 where it normally is at temps.

To top it off, got a flat tyre which needs replacing too.

I have had exactly both these scenarios this weekend - both.

Seems a pattern building. Over 10 days just to get it actually into Tunbridge Wells Audi. Poor service.

Last time it went there one of tyres came back 1 bar higher than it should have been. Clearly well road tested as warning came on immediately I left forecourt

How long is the UK warranty ?

[Tweaky]

I have just developed the same fault with my car, but have to now wait 3 weeks or so before it is safe for my local dealership to reopen and check it out. I did connect up with my OBDeleven, and it did say somthing about a faulty sensor along with a couple of other warnings, one of which was somthing about a cylinder sensor.

[Brooner]

I just had this starting with me
So will get it in to be sorted already explained to Audi its a common fault and it is the thermostat that is sticking
so will see if they have one in stock