ent

I've read through the pages and pages about engine hesitation and stumbling but I've noticed something a little different with my 2014 PDK C2. Under hard acceleration from a stop, the car starts moving briskly and the engine accelerates quickly to about 4k rpm. At that point, the engine hangs at 4k for a half second and then resumes accelerating quickly. I took the car to the dealer and was told this is normal. Have others noticed this behavior?

mmaturo

Your comment goes to the other half of the discussion in many of the same threads where the engine has a switch over point (but at lower rpm) that causes a short plateau in cars. Variocam transition. That though is around 2800 rpm. Keep reading, there is posts on this too. Mine does the roll off hesitation a lot but not the later dip. I have not seen a clear resolution though.

On the roll off hesitation at least my car is getting better since I have been flogging the heck out of it the last couple of weeks and leaving it in sport mode and keep doing the throttle reset thing with the ignition key. Adapting the pdk to aggressive driving seems to be helping in other words. But I still doubt what the car is going to do. I mentioned it to the dealer when I dropped off the car to do a quick check on my engine cooling fan functions as my car tried to overheat two weeks ago (air shut off and temps climbed fast into upper 200s in 95 degree weather) but fixed itself. The service manager no less said it was the pdk actually sitting at a stop in second gear and not first and then doing a switch back to first at roll off causing the sensation. Um ok. I will let you sort that out when I drop off the car for a more complete service or issue.

ent

Thanks for the response. I have read about the hesitation at around 2800 rpm but mine is at decidedly higher rpm. I guess the lack of replies means that my situation is either so common that others don't even think about it or so rare that no one else has experienced it.

ignacio

no pdk glitches!

Archimedes

I haven't noticed that, but I have noticed in both my 991 and 981 that the PDK needs to warm up before it shifts quickly and cleanly. The shifts I get in the first few miles of driving are noticeably slower and lazier than once the car is warmed up, even if I push the car right away.

WCE

Clutch slips until that ~4k rpm point in first gear with the ECU limiting revs, clutch is fully engaged afterwards - just like you would try to do while driving a manual gearbox!

ent

Thanks for that summary. I thought that clutch engagement might be the explanation. Just didn't think it would be so noticeable or occur at 4k rpm.

GrandLaker

Can you elaborate on what this throttle reset process is with the ignition key?

zathras

Turn the key to the on position but do not start the ignition. wait 60 seconds, turn key off. Do not touch any pedals during this entire operation. Supposedly this does the 'throttle reset'. I was told this by my service rep at the dealer.

Optional- keep one eye closed and chant "there is no substitute" over and over during the process.

mmaturo

this. including the last part. do both.

GrandLaker

Cool, thanks guys!