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I've noticed that sometimes in my 2012 CS with 7MT, when I'm at a standstill in neutral, and then shift to first there is a deep thud sound. It happens about 25% of the time. Normal? or is a trip to the dealer in order?

Needsdecaf

Has not happened on mine.

When you are standing still in neutral, is the clutch in or out?

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Neutral -> Clutch out -> Push clutch in -> Shift to 1st *thud* -> engage clutch and drive

GregD

I think I've felt that occasionally in 1st and second... After 90 minutes spent in bumper to bumper traffic the other day I also had time to reflect that the grab point is very very low on the clutch pedal travel. So for grins, make sure you jam the clutch pedal *all the way* and see if it still does it ?

LexVan

My guess, the hill hold function is engauging, and you're on an incline "about 25% of the time".

And you're sure it's not related to auto-stop-start?

Code

This happens on flat surfaces the vast majority of the time. auto-start-stop is disabled.

I'll try what Greg suggested to see if maybe its just user error. Hopefully that's all that it is.

Needsdecaf

Hope so.

008

Probably just a little drive train lash.

AG911

My 2012.5 7mt does the same. This happens when you quickly shift into 1st from neutral. But if you slowly or gently shift, taking your time, you can avoid the thump.
I've taken it in before and the tech said it's "normal."

Jabs1542

This has been covered in another thread, sorry I couldn't find it, I tried

First the sound: Are you referring to the thunk you hear after you engage the clutch at the moment you feel the gear engage? If so then this is most likely normal behavior - there are a lot of us with this issue (thus the other thread I couldn't find)

Possible cause: Remember that the 991 MT is based on the PDK transmission, as such it has two main drive shafts (not sure what the official name is, but you get the point), one for the odd gears and one for the even gears. When you approach a stop light, put the gear box in neutral and wait for the light, the drive shaft loses its spinning momentum and stops. Now when you engage first gear, with the clutch in, the gear synchros cause the drive shaft to spin up a bit, their synchronization and engagement is the 'thunk'.

The experiment: I found this interesting in my car, you need an open space to try this.
> Roll towards a stop in 2nd gear, slip the gearbox into neutral, come to a complete stop, push clutch, and engage 1st - I get a 'thunk' sound.
> Roll toward a stop in 3rd gear, slip the gearbox into neutral, come to a complete stop, push clutch, engage 1st - I get no 'thunk'.
> Roll toward a stop in 3rd gear, slip the gearbox into neutral, come to a complete stop, now sit for at least 30 seconds, push clutch, engage 1st - I get a 'thunk'

Note the YMMV: You may referring to a different sound, or your car may not has the 'feature' I described. But others have and it's been covered somewhere else in the depth of RL threads.

Happy hunting

LexVan

Maybe these??:

https://rennlist.com/forums/991/9458...se-please.html

https://rennlist.com/forums/991/9080...ion-clunk.html

Jabs1542

The second one, thanks Lex

Needsdecaf

One thing I noticed on this car that was kind of different for me was that it doesn't mind going into first at speeds under 10 MPH or so. And it doesn't like a rolling start in second from about 5...,not enough torque.

As a result, I find myself slotting it into first as I roll up to a stop, foot on brake, clutch depressed. If I can go quickly I go, or briefly hold the clutch. If it's a long wait, I'll shift to neutral and clutch out.

Perhaps it's because I am shifting to first while still in motion that when I shift to neutral and back into first that I've never heard a clunk?

Jabs1542

Based on current theory, which seems to be holding true, that would be the case - no clunks for you as long as you pass through first while still in motion

Needsdecaf

Good to know!

I will play around with it this weekend and see if I get any clunking but I haven't noticed any to date!