Transmission failure within 30 seconds of passed MOT...

Hi all, I'm new here, but have owned my 99 C2 Tip Cabrio for 4 years now. Hoping somebody can help clarify my thoughts on this one. Passed MOT on Saturday after about a year stood on my drive while I did a few suspension and brake maintenance jobs that got delayed by a new baby and a load of budding work. On the way to the MOT I remembered that just before I parked it up it had been flash D-4 on the dash. No response from steering wheel buttons but seemed to drive okay otherwise. After MOT (pass with no advisories ) it was reversed onto a slope and let running while I got the keys and got a bit of stick about my hairdressers car, then I jumped in, put it into reverse and it stalled. Tried to restart, nothing, just stopped dead. Lights on but nobody home. Left it 5 minutes and it started got it into gear and went on my merry way. So I'm thinking probably low At fluid, giving the issue before hand, then made really bad by parking on the slope sloshing all the fluid forward. So I'm planning a transmuison service. Any tips on what fluid to use? And is the renntech guide correct that the 986 filter is the same as the 996 even though its less taht half the price on design 911? She's been off the road well over a year and I'm desperate to get her out on the road again!

Not getting a lot of love on this one, so maybe somebody can just check my home work for what I need for a transmission service for a 99 3.4 C2 Tiptronic. Oil - I believe OEM is LT71141 - this one appears to be compatible, although The Gulf Multi Vehicle is recommended elsewhere. 2x 4l https://www.eurocarparts.com/ecp/c/...atic-transmission-fluids/?522776291&0&cc5_869 Filter - 986.307.403.00 (this one I'm not sure of, but it's the one they say to use on the renntech "how to" guide - a bit odd that design911 don't list it? Gasket - 986.397.016.00

I'm not sure about the 996.1 gearbox, bit the .2 is a Mercedes box. Even then, all I ever found was "Dealer only" or "Special oil" the Gulf multi ATE is compatible with the MB236.10 standard (which has been superseded by 236.14) but I don't know about yours, sorry!

The first thing I would check is the transmission shift microswitches on the gear selector, is it showing that the correct gear is selected on the dash ? It won`t hurt to do a transmission fluid and filter change though :thumb: Sorry no idea which fluids or filter are required as I don`t have a tiptronic.

996.1 has a "ZF" box as far as I can tell. OEM fluid is Esso LT 71141, interestingly this isn't mentioned in any of the oils I can find on euro car parts or Design911, but if I search for it separately its there listed in one of the multi vehicle oils. I think I'd rather risk 50 quid on this stuff than have to spend 300 at porsche! Forgot to mention, Shift Lever has just become quite stiff too. I shouldve got a manual :frustrated: Thanks for your replies

That is a classic symptom of the linkages/microswitches not being quite in alignment, so I am lead to believe, so the transmission goes into limp mode. You need to check out the linkage and microswitches :thumb:

Didn't post as didn't follow the logic really. IMO lack of fluid/old fluid wouldn't have caused the car to stall. Thats more likely to be a vac leak in the engine. Other symptoms are suggestive of microswitch/linkage issues as already mentioned. Tip trans oil/filter change isn't difficult, kits are readily available. I'd double check which oil is needed with your local indy however. :thumb:

Hi Check the rubber grommet in the end of the cable at the gear box end of the shift lever, where it fits over the switch on the side of the gearbox if there is a lot of slack the gearbox won't be able to select the gears properly hence flashing lights, a new end piece is only 30 quid Early 996 ZF transmission is used in lots of vehicles, Audi Bmw Porsche Vw Fluid is the same porsche pt number 000 043 205 09 boxster porsche pt number 000 043 205 09 996 Boxster filter is 986 307 403 00 - 996 filter is 996 307 403 00 996 filter has additional bracket baffle fitted to bottom side - check ebay for pics and prices I'm about to change the fluid in mine Gasket for sump is 986 397 016 00 cheaper on ebay collect from eurocar parts Bill

98632561201 Search this number on design 911. Its the part that causes your problems, it fits over the gear selector shaft on the ourside of the gearbox, it suffers from corrosion and it's easy to change

I Agree with the above comments ... so ill just add ... You parked it up with a fault a year ago .. may be intermittent a year ago ... The car had the tiptronic box in limp home mode .. there was a fault basically . From the description it's either the multi function switch on the box or a very stiff linkage causing it not to register as in gear .. the pivot linkage on the box needs freeing off basically .

On mine the aluminium rivits corroded out and the two halves parted, as this sits over and is engaged on the selector shaft i can imagie how this could cause the stifness as the internals displace. I was lucky enough to be able to put all the pieces back together and use screws instead of rivits. This also has the starter inhibitor built in so that may account for your non stating until you moved the lever and cycled the switch again.

Thanks guys, this is starting to make sense now. The car lived on Guernsey for the first few years of its life so it has a more than its fair share of corrosion from all that salty air. I'll get it up on stands this week and see what I find underneath. I will probably still go ahead with a fluid and filter change just so it's ticked off. If I can stop confusing myself looking at oils!