Tiptronic Slipping
 

I recently bought a '99 Boxster. The tow guy must have attached something on the rear control arm which caused it to break, due to this control arm failure the axle bearing broke as well.

When I got everything fixed my tip showed the following codes:
3rd. and 4th. gear ratio incorrect

I cleared the codes but the tip seems to slip on 3rd gear. It will shift from 1st to 3rd but in 3rd gear it only revs and feels like slipping, won't go past 40mph.

I checked the tranny oil and looks very dark, will make a tranny maintenance and see if that fixes the problem.

Anyone any ideas or tips?

if it were mine i would take it to the dealer. i think their scan tool /programmed is needed. i WOULD NOT drive it or use the same towing service

Dealer Diagnostic
 

Thanks extanker, I already did. Their first diagnostic was that the DME or the Tip module was faulty. I have read the problems that a dyno can cause and suggested to reprogram the units. Apparently they did an now they say there is no electrical problem and maybe a mechanical.

Does anyone has had a problem like this? A faulty speed sensor perhaps?

My TIP starts out in 2nd gear in the drive mode. I was experiencing sudden hard down shifts at low speeds and I have heard and read that when the TIP is low on oil you get weird things happening. When I drained the TIP oil it was very dirty and I only got about 3-4 liters out. After replacing the filter and cleaning the sump and pumping 4 liters cold. I then warmed it up to 90 degrees and pumped in another 1 1/2 liters, the did the shift stage and then pump in the rest while the engine is running...took 6 liters total. Now it shifts smoother and seems more responsive, especially in manual mode.