kosmo

i've been noticing something usual after intital start up. When in AUTO mode its seems like there's a delay (about 2 seconds) before the PDK engages 1st gear. To clarify, I get the sense that the clutch is not dissengaging to my throttle input. This has only happened about 5 times now and always after intital (Cold) starts but it has gotten my attention now. I have 10k on the car. Anyone else experience this?

timmp

When I select reverse to back out of my garage in the morning, PDK works perfect, but, when I reach the street and select Manual drive, it will hesitate to engage unless I let it sit for a moment after selecting drive, and before giving it any throttle.

While annoying, I had the first gen bmw SMG, and frankly, PDK is so much better in every sense that this one "glitch" doesn't trouble me (call it reduced expectation, given my experience with these automated manual gear boxes).

tim

stevepow

The clutch is normally slightly engaged in PDK even at stop to create "crawling" (or "creep" depending on which document you read) mode.

If you are on a hill, hill start can grab - but that's cold or hot. How cold are you talking about? Cold cars (been sitting out at 32F or lower) always seem "cold" to me - meaning they don't seem as smooth and ready to go right off. I don't notice anything particularly odd though with the PDK.

ADias

This is normal behavior. If on is a bit more aggressive with a resolute stop (brake) backing up and accelerating moving forward that is reduced or eliminated.

I suppose it has to do with the fact that reverse and 1st are on the same shaft and share the same clutch (see below), so there's no dual clutching (in the normal sense) at work there.

kosmo

by cold i mean at 1st start in the am. Its happend in every season. I only mention this because its seems like its occuring more often-seemingly.

964C4

Yes, it has happened to me also on cold start and after the car has been sitting for a long time (1st gear or reverse)

mdrums

There is nothing wrong with your pdk. Its cold for 1 thing and pdk is not really a tranny and will never act like one

ADias

A PDK is not a tranny ?!? I imagine, Michael that you meant it's not a manual tranny. I would argue that it is an electro-mechanically actuated manual tranny. And as a manual tranny (i.e., without a cushioning hydraulic torque converter) will, when cold, be slightly harsher, as a manual tranny is.

Bijan

Sounds like the "drive off assist", brakes are applied for an extended 1 or 2 second if first or reverse gear is selected on an incline

stevepow

I have been trying to pay attention to this lately and still can't say that I can replicate what you describe - even on a quite cold start up. I have about 9K on mine now. I guess you could just wait to see if it gets worse and deal with it under warranty if it does.

Adias brings up a good point about how PDK operates too.

Chris from Cali

The mistake is driving PDK in auto mode.

stevepow

I don't think so. I normally stay in auto while the car warms up to prevent myself from over-revving it - my self-discipline is not so great some days.

And Auto or not, you have to manually shift from R to D regardless. While I could imagine some subtle differences in the computer programming, what else can the car be doing when you go from R to D while stopped? I think it has to go into 1st no matter what.

mdrums

LOL...typing late at night on the iPhone...I was trying to say PDK is not exactly a automatic tranny...ya know like most people think it is and think it would feel and act exactly like a auto tranny.

stevepow

And thank God for that.

8 LEGS

I am having the same problem. Almost always when the car has been sitting for awhile, which means it is almost impossible to replicate for a mechanic. Mine is a 2012 so i am just about out of warranty.