2016 A5 Unknown Clutch Issue

[RLeafy]

Have a family member with a manual 2016 2.0L Diesel A5 34k miles and recently in some start stop traffic she went to move off and the clutch would not lift off the floor. Got it moved to the side of the road and recovery out, AA guy put some clutch fluid in and pulled the clutch off the ground, started moving and got the car to audi.

Audi checked it over and they said they couldn't find an issue with it, their only answer was that it may have overheated but they reiterated that they weren't sure.

She is now driving only when it's an absolute necessity and is very frightened of driving it.

A similar issue happened last year however the slave cylinder had failed which seems like a known issue in these cars.

Any thoughts on what the issue may have been? Felt like Audi only said overheating to give some sort of answer but it could be completely reasonable for all I know! Just seems strange that it starts overheating at 5-10mins of traffic, without a clear cause of overheating and how to avoid it in the future. Thanks!

[cliffcoggin]

Ryan.

The only reason for a clutch to overheat is slippage, caused either by poor driver control or severe  wear. If you can eliminate those factors then there must be a fault in either the master and/or slave cylinder.

How many miles has the clutch done? Does the driver ride the clutch at junctions etc? Is the clutch "bite point" about half way up the pedal travel when it is working? Does the engine speed increase without a corresponding increase in road speed? Answers to those questions will us identify where the problem lies.

[RLeafy]

The clutch has done all 34k miles the car has done.

She doesn't ride the clutch but while in gear and moving she keeps her foot with a slight bit of pressure still on the clutch, not enough to move the pedal but definitely in contact. This is what I thought the issue would've been caused by however she has been driving est 25 years and this hasn't happened before, unless this car is just more sensitive? She has driven both a manual A3 and A1 for a number of years previously.

The bite point is normal and the road and engine speed feel like they increase/decrease at a normal rate when I drive it.

Thanks Clifford!

[Stevey Y]

1 hour ago, RLeafy said:

The clutch has done all 34k miles the car has done.

She doesn't ride the clutch but while in gear and moving she keeps her foot with a slight bit of pressure still on the clutch, not enough to move the pedal but definitely in contact. This is what I thought the issue would've been caused by however she has been driving est 25 years and this hasn't happened before, unless this car is just more sensitive? She has driven both a manual A3 and A1 for a number of years previously.

The bite point is normal and the road and engine speed feel like they increase/decrease at a normal rate when I drive it.

Thanks Clifford!

Hi I would say that there is air in the clutch line but most likely the master cylinder for the clutch is failing, the most common cause is bad fluid where no one bothers to change it, if you replace the clutch master bleed the whole braking system with comma ESP4 and the clutch cylinder, any contact however light will force the release bearing on to the pressure plate, thats why they supply a foot rest.

Steve.

Steve.

[cliffcoggin]

Fair enough Ryan.

I have reservations about resting a foot on the pedal at all times. My driving instructor (my father) would slap my leg when I did it, but I daresay that behaviour would be frowned upon now.

Nevertheless I reckon it's more likely to be a fault in the hydraulic system such as air or worn cylinder seals.

[RLeafy]

Thanks Guys!

Air/ a fault in the hydraulics makes sense to me most, especially given the recovery guy managed to pour more fluid in, just frustrating that Audi couldn't solve it. I'll get it checked in a mechanics and see if they are any more useful than Audi was.

I've said to her about resting the foot on the clutch but I suppose it is a habit at this point, unfortunately!

Thanks again, appreciate the info.