Jerky Triptronic Shifting - 986 Forum - The Community for Porsche Boxster & Cayman Owners

Britrover · 02-20-2015, 03:54 PM

Hi,

Our 98 Boxster with 80K miles exhibits jerky shifting from 4th to 5th and hard down shifting of the gears. I just had the dealership change the fluid, and it has made a slight difference.This is our first Porsche, so my first question is if this is normal behavior in these vehicles? If not, what are the other areas that need to be looked into? The motor mount on the vehicle needs replacement, so not sure if the jerky shifting is correlated to that, but getting that sorted next weekend. Is there anything else that needs to be looked into? For instance, do these vehicles need a software update for this issue? Could this be a dirty throttle body? Also, if this more of a TCU or valve body issue how would one isolate it and how much should I be looking at to get the TCU or valve body issue sorted?

Britrover · 02-20-2015, 04:10 PM

I also need to validate if this issue happens in the Manual mode, hopefully that will be a temporary fix

.

mikefocke · 02-20-2015, 04:21 PM

Normal no. Owned a '99 TIP and a '01S TIP and they were smooth between all gears.

Britrover · 02-20-2015, 04:40 PM

Thanks for your response. Will wait for others to chime in so I can isolate and fix this issue.

Retroman1969 · 02-20-2015, 05:23 PM

My TIP is smooth most of the time, but does occasionally slip or shift hard (or not at all) between 4th and 5th. In manual mode it's fine.
The shop suspects it's a sticky valve in the trans. When they changed the fluid awhile back, they noted that it was very dirty (but not burnt) and had likely never been changed. Lots of driving and a couple of more fluid flushes/changes will hopefully free it up eventually.
Durametric scan showed the issue was not electronic.
This might be your problem as well.

brjak · 02-22-2015, 08:06 AM

What was the cost of fluid change?

Nine8Six · 02-22-2015, 11:28 AM

There is a vacuum activated valve for the coolant to cool down the tip. That valve can go bad... mine was seized shut causing some of the gears to slip when car & tip were hot (mostly 4th to 5th). No jerky upshift... just slipping a tad but like yours I had occasional clunking sounds when downshifting tho :/

Changing that tip vacuum coolant valve thingy fixed it, apparently, never had it again. Whatever that valve is called, your indy should know what to look for (really forgot the name for that thing). Cheap, $45 or something.....