RS246.com Forum :: The World's #1 Audi R, S and RS Enthusiast Community

Starting to have an issue when setting off the car seems to struggle selecting 1st-2nd gear resulting in the revs spiking and then it bangs into 2nd and then everything fine after that. Doesn't seem to repeat all the time but it seems hesitant to select correctly at times. Didn't make a difference which mode I was in and would get the issue in tiptro too.

Did a VCDS scan and I get a code on the ABS module:

01119 - Gear Recognition Signal
35-10 - - - Intermittent

Googling has returned results from new gearbox to new F125 switch. I'm inclined to try replacing the latter however what exactly does the F125 switch actually do? Would it be connected to a dodgy shift between 1st-2nd?

Just to add a few things into the mix, I also have a constant low level shake through the car when moving. I've had everything checked on the suspension and driveshafts, swapped tyres/wheels and still not able to pinpoint it. To me it feels like it is through the drivetrain, so a possibility it could be linked to my issue? Also noticed a whine that rises and falls with the revs, more likely alternator than something from the box?

What I'm probably doing in this post is trying to talk myself out of the fact the box could be pumped

Exact symptoms to my failed box. Opened it up and metal shavings all in the fluid, complete clutch pack failure. Time for a rebuild and upgrade!

Did you have the code?

If your clutch pack went which is a mechanical item I'm surprised there was that specific code and the symptoms were more like bad slippage than a banging into gear? Mine doesn't seem to slip it's just the transition between 1st-2nd every other gear is fine. If the selector switch (F125) has anything to do with this or can be a dodgy solenoid in the valve pack I'd rather replace them than just replace everything in a gearbox rebuild.

TBH if it is the gearbox spending £4K on a £7K car doesn't make too much sense to me. I bought it full well in the knowledge that if the gearbox went then I wouldn't let my attachment to the car lead to spending lots of money on it that is never seen back (been there done that a lot of times).

However I do not mind spending a bit of money and time narrowing it down so I can confidently say it's properly knackered.

Gripper1 wrote:spending £4K on a £7K car doesn't make too much sense to me

It's not a car, it's a C5 RS6. There is a difference....

I can see where you are coming from, it does have a certain thing about it. I looked at the C6 RS6 and it just doesn't have the same specialness about it.

But I I was to sink £4k into a new box it would be a low mileage weekend only garage queen. Mine is more a car that has been driven and enjoyed. At 125k miles how much more will it do before other more expensive problems rear their head? Despite This would be box no3 if I was to replace, sometimes you've got to be realistic.

Spoken to a few auto transmission specialists and of the 3 I contacted 2 came back with the same diagnosis of a seal gone in the forward drum. I have no idea how an auto box works so unable to elaborate but maybe makes sense to some?

Just a quick question, but would oil starvation lead to this problem, I find it a little coincidental that 4k after a gearbox service it gives up the ghost. The current box has done approx 55k and felt strong until the shaking started 1000 miles ago and the missing of gears the last 200

I found a faulty F125 switch caused the dash board to light up like a christmas tree....I also had the same gearbox problem, no fault codes as such but i did have to get a new box...metal in the filter too.

Car has been stood for a while and prior to a holiday where the extra space of the RS6 would come in handy I decided to have a look into the gearbox issue.

Dropped the gearbox sump and oil seems to be fine, but the filter was cracked. I also didn't get much oil out of the box, maybe 4l at most. Got a new filter and checked the pickup was the correct length. Put it all back together and refilled getting much more oil in this time.

Gearbox is now fine, shifts smoothly and doesn't slip anymore. Very glad I decided to look into it myself, every garage were instantly intent on pulling the gearbox for a £4k rebuild without checking the basics.

Took it on holiday, 600 miles in and I've blown up the rear diff! But at least now I know what the long term slight vibration was that had alluded me for a while!

Hope this is useful to some just in case they think the worse of their gearbox

Awesome result. Well, apart from the diff grenade.

Lesson here for everyone.

What caused the diff to fail?

Has anyone changed their rear diff oil? Surely it needs changing every now and then - but not sure how often.

I had the diff oils changed out not so long back. But I guess an un noticed leak could quickly result in a dry differential. One of my old posts was about a slight vibration that felt like it was something through the drivetrain. Buy no one could pin point anything.

Still to get proper diagnosis, but it initially sounded and felt like a sticky caliper on the rear. Then 5 mins down the road a pretty horrible mechanical noise like a bag of bolts from the rear of the car and a loss of drive.

Car is currently getting transferred back to Scotland. I've got a metallic turd brown, diesel Citroen C4 to tide me over till the end of the holiday.

Can a diff be rebuilt or is it a new from Audi job?