Help needed! 2018 A4 1.4 TFSI Clutch problem?

[ahm]

Looking for some thoughts on a technical issue starting to show on my car. A 2018 Audi A4 (21 months old) 1.4 TFSI Manual BE Avant. 2 year PCH car so due back soon! Only 14000miles on it.

Anyway, during anything more than 'very gentle' acceleration in 3rd and 4th gears (not noticed in other gears yet, but might be present) the car seems to slip out of gear or something for a brief second. Revs become 'jumpy', jumps up the revs as if it's slipped out of gear (and numeric gear indicator goes blank) and then comes back to normal, gear indicator showing selected gear again. This can jump about like this for a second or 2 or until I release the accelerator v slightly

Anybody any ideas what it could be. Obviously car's still under warranty, but I know when it comes to clutch issues it's not guaranteed to be covered by warranty. Car due back in July, due service in June. If BCA were doing collections am tempted just to end lease early and hand back, not using it much at moment. Though may guy who collects it might notice it.

[sliks]

Its either gear linkage (most likely), engine mountings (shouldn't be at that age) or syncromesh (inside gearbox) (unlikely)

I doubt it'll be noticed by collection driver especially if it is bca collecting unless it is specifically due an inspection

Has any work been done on the car previously?

[sliks]

Wait... Does it jump out of gear or do the revs just rise without vehicle speed increasing? That's a slipping clutch

[ahm]

sliks said:

Wait... Does it jump out of gear or do the revs just rise without vehicle speed increasing? That's a slipping clutch

On acceleration when revs hit between 2000-2500rpm, revs jump about 500rpm without acceleration (at same time the gear indicator on dash disappears) then drops back down a fraction of a second later and indicator shows gear again. Can fluctuate like that a little but for a second or 2 and then I seem to either accelerate past it or stop accelerating and it recovers. Seems intermittent, doesn't happen every time.

[sliks]

ahm said:

On acceleration when revs hit between 2000-2500rpm, revs jump about 500rpm without acceleration (at same time the gear indicator on dash disappears) then drops back down a fraction of a second later and indicator shows gear again. Can fluctuate like that a little but for a second or 2 and then I seem to either accelerate past it or stop accelerating and it recovers. Seems intermittent, doesn't happen every time.

Intermittent problems are harder to diagnose but there is a few easy things we can do to narrow it down.


See if it still does it if you keep applying pressure to gearstick in 3rd and 4th. Positively keeping it in gear. If it no longer does it - it means linkage or synchro need looking at

To test a slipping clutch, on a flat level road put vehicle straight into 5th gear at 30mph and try to accelerate. If it slips then it is the clutch slipping, if the engine and gearbox remain locked together then clutch is not slipping

Finally if it has only started doing this recently try to see if you can physically see the clutch master cylinder and slave cylinder, see if there is any signs of slight oil leakage. It's unlikely as a cause on such a new car but manufacturing defects do occur. Any oil mist/leakage would mean air getting in the hydraulic system and causing clutch to stick momentarily randomly otherwise feel normal.

[ahm]

sliks said:

Intermittent problems are harder to diagnose but there is a few easy things we can do to narrow it down.


See if it still does it if you keep applying pressure to gearstick in 3rd and 4th. Positively keeping it in gear. If it no longer does it - it means linkage or synchro need looking at

To test a slipping clutch, on a flat level road put vehicle straight into 5th gear at 30mph and try to accelerate. If it slips then it is the clutch slipping, if the engine and gearbox remain locked together then clutch is not slipping

Finally if it has only started doing this recently try to see if you can physically see the clutch master cylinder and slave cylinder, see if there is any signs of slight oil leakage. It's unlikely as a cause on such a new car but manufacturing defects do occur. Any oil mist/leakage would mean air getting in the hydraulic system and causing clutch to stick momentarily randomly otherwise feel normal.

Thanks very much. Had to nip to work this morning so was able to try it out. Pressure on gearstick didn't prevent it. Was doing the 5th gear thing and all seemed fine. Then it randomly happened once. Then got to a hill and it kept happening in 3rd and 4th, but not in 1st or 2nd. After hill it happened during a couple of 5th hear tests but ok after again. Was better on way back home, maybe cause car had warned up (was only a 8 mile round journey). Other thing I noticed is sometimes the gear indicator disappears when it happens, other times not.

Just debating now whether to chance handing it back to BCA when they start collecting, or get it looked at by Audi. 14000miles is ridiculous if a slipping clutch, but still know it would be an arguement with them to try and get it warranty claimed.

[ahm]

Also noted my oil level is low, just about at the minimum mark on the mmi, but no warning yet. I'm assuming it would not be linked, but just highlighting it. Ordered some oil for delivery later in week.

[sliks]

ahm said:

Also noted my oil level is low, just about at the minimum mark on the mmi, but no warning yet. I'm assuming it would not be linked, but just highlighting it. Ordered some oil for delivery later in week.

It could be linked, If oil is say leaking into bellhousing it could foul the flywheel and clutch.

The clues for that would require an inspection underneath the vehicle for signs of oil where the gearbox is bolted to the engine. With undertrays a smaller leak would not show up on your drive for quiet some time.
Oil should be checked at least 5 mins after turning off the engine, this allows the time for nearly all the oil to gather back in the sump where the measurement is taken.

[sliks]

ahm said:

Thanks very much. Had to nip to work this morning so was able to try it out. Pressure on gearstick didn't prevent it. Was doing the 5th gear thing and all seemed fine. Then it randomly happened once. Then got to a hill and it kept happening in 3rd and 4th, but not in 1st or 2nd. After hill it happened during a couple of 5th hear tests but ok after again. Was better on way back home, maybe cause car had warned up (was only a 8 mile round journey). Other thing I noticed is sometimes the gear indicator disappears when it happens, other times not.

Just debating now whether to chance handing it back to BCA when they start collecting, or get it looked at by Audi. 14000miles is ridiculous if a slipping clutch, but still know it would be an arguement with them to try and get it warranty claimed.

Suggests it is a slipping clutch, is it getting worse with time? Phone Audi and see what they say, they may cover it fully and get it done during lockdown

Also about the gear indicator is it the gear change indicator that is fitted to this car? Tells you to move up or down?

Edited by sliks on Tuesday 21st April 13:34

[ahm]

sliks said:

Suggests it is a slipping clutch, is it getting worse with time? Phone Audi and see what they say, they may cover it fully and get it done during lockdown

Also about the gear indicator is it the gear change indicator that is fitted to this car? Tells you to move up or down?

Edited by sliks on Tuesday 21st April 13:34

Yep, the indicator that suggests when to change and shows current selected gear.

[ahm]

And one other unrelated query. I had a look round engine, but tbh I've no idea what I'm looking at which doesn't help. But one thing that stood out is one piece very rusted. Visible between the covered main engine and the coolant reservoir. Just stood out as the only rust visible anywhere on car. Know what it is?

[sliks]

It's a flange shaft, connects to driveshaft. The bright surface rust shouldn't be a concern. That will continue to do its job for a long time

[sliks]

ahm said:

Yep, the indicator that suggests when to change and shows current selected gear.

As far as I know it's a calculation by the dash, like fuel consumption figures, range etc. Gears can be worked out using revs, speed and the box's gear ratios.

[ahm]

sliks said:

As far as I know it's a calculation by the dash, like fuel consumption figures, range etc. Gears can be worked out using revs, speed and the box's gear ratios.

Yeah, never paid much attention to it. Just noticing now that it shows what gear your in when driving, and it disappears when the issue is showing.

[sliks]

ahm said:

Yeah, never paid much attention to it. Just noticing now that it shows what gear your in when driving, and it disappears when the issue is showing.

Just paid attention to my own (vw) for the first time - it's not fooled by no load conditions so I guess it's using the mpg info.