Complete tiptronic failure?

Hi guys, Driving on the motorway yesterday I accelerated to move in to the outside lane this caused a kick down on the tiptronic box which seemed to just let 4th gear slip, revs increased no speed increase, eased off back in 5th all good, then it happened again this time flashing R on the dash. Pulled into services switched engine off filled her up restart fine.. then in traffic as we slowed down all fine then speeding up it just seemed to slip in every gear could only accelerate slowly this time we had a flashing D and 4.. The car now runs and creeps forward any throttle input it slips, the local garage that it got taken too diagnosed a complete gearbox failure, is that possible so quickly within a few miles? fluid levels are correct The car is a 1999 c4 cab with 60k miles Regards slow M

Hi Sorry to hear about this. I am going to chip in because I have two Tip Porsches from this era and have read a lot of posts about problems with them over the years. Not because I actually have had this issue. It sounds like the box is going to have to come out. Either the torque converter has failed, or the gearbox has lost pressure internally. The converter is an easy swap once the box is out, but you need a proper diagnosis. Has anyone read the codes yet? On the plus side there is a lot of "while you are there" things you can attend to. I had the Tip box out in my 986 about a month ago. What are you like with a spanner? Its a doable DIY. Edit: It is unusual at such low miles. Mine have 195k & 131k on respectively and many people have more. It's just bad luck. All the best Berni

Bit of an update.... just driven the car seems to drive quiet normally but quiet clunky selecting drive and on some of the up and down changes but seems fine can the transmission fluid over heat on these?

I watched a wheeler dealer recently where they had a Tiptronic problem. They replaced the transmission fluid and cleaned any filters and it worked fine. Only a thought

Had the filter and fluid on mine changed very recently at 94K and the changes are much quicker and smoother.

It sounds like the tip box fluid and filter needs to be replaced. Fairly common issue. Especially as these cars are getting older and most tip boxes never see their fist service until they start going wrong. Fluid change and filter is not a big job at all.

The garage would have looked at fault codes .. what these are will point you in a direction wether its a pressure failure or perhaps a torque convertor issue .. only code for this will be lock up clutch though . Basic rule of thumb .. Change the oil and filter .. Change the valve body .. Change the gearbox . Valve body or brake bands would be my guess . I watched that wheeler dealers episode .. they did something on the exhaust which i forget .. but i do remember laughing at the time .

From memory there was a rattle at the back and he went around knocking everything until he checked the CATS last. The CAT was shot to bits and sounded like a box of corn flakes when you shake them, god knows why he went there last, he knew it was the CATS at the beginning.

Thanks for all the help guys, Little update again extended drive yesterday, seemed to calm down even more threw a little wobbly just showing D briefly, I'm now wondering if the extreme heat of friday was an issue and 2 hrs on the A1? (Wishfull thinking!) So stuck in Yorkshire attempting to drive back to London today if you see a black c4 on the hard shoulder give me a wave!😄 Mike

Good news. I'd get that fluid and filter changed at the least. If the fluid's low (when was it last checked?) it would overheat more quickly. ETA: sorry I see you say levels are correct. Still worth doing I think.

Hi Slow M I re-read your thread and can think of another possibility. There is a "multifunction" switch on the side of the gearbox which is connected to the selector and tells the box which gear you are in. When these fail the gearbox can really freak out because it does not know which gear you are in. You have had various flashing gear selections (inc "R") so maybe you will be lucky and it will be that. Symptoms can include a loss of drive, loss of power harsh changes and so on. Best of luck! Berni

Hi guys just an update, Took the car to a respected indie, the car was driven (ive noticed that it now runs hotter than it used too) until it slips but no fault codes showing on the computer, they've suggested maybe the torque converter is at fault or gear box they're going to investigate and let me know.. I'm wondering now on a car of this age and value if its actually worth pursuing the above repairs if the car needs it?

Hi Sorry to hear it is not something nice and simple. Maybe now is the time to start a COVID project? Berni

Just thought I'd bump this too the top again So after a bit of research and getting some very expensive quotes for a rebuild I stumbled across a company called JT automatics in Erith, they seem to repair everything from rolls Royce to Aston Martin after a chat they reaveled they are zf specialist and the owner actually used to own a C4s and knows the cars well, they came across totally professional and great people too, the car was collected by them, the breakdown truck driver also owns a 2000 c4! So away it went. On collection I was informed that it had already been rebuilt about a year or so ago but incorrectly reassembled that caused some sort of oil starvation which then caused the clutch pack to disintegrate! The car is now transformed drives totally different no sort of clunky shifts up or down or hesitation on kick downs So cost... including gearbox removal and replacement new clutch packs, seals, bearings bushes gaskets and rebuilt torque conver was £1940 +vat compared too some quotes of 4.5k ! It seems like a bargain, so the girl lives again!

A very sensible solution. The ZF auto box is used across several marques, so clearly there is a market for specialists who deal in these boxes. They do volune, they see a span of faults and develop a fompetence for diagnosis and fixes. Unlikely any Porsche specialist would have the experience of volume and hence an element of trial and error at your expense is very possible. I am pleased for you. Total outlay at less than £2.5k is very little for this kind of work.