XSeries-forum

Overall car drives fine no concerns when abused it's like a scalded cat!

However, on a sensible driving day, once up at cruising speeds 60/70mph and settled into the cruise (no cruise control in use), when light power is requested car stumbles and gives hesitance / vibration, push the pedal further to kick down point and a gear is dropped and away it pulls.
It does not present itself in DS mode


A possible imaginary fault though it does give concern.....

My thoughts are mixed & looking for pointers?
Initially thought about swirl flaps, gunked manifold etc though flaps are inactive below 2000rpm (???) the Rev range of this troubles seems to be circa 1400-1800rpm. Is that where the first turbo spools ?
Maf sensor fault ?
Dpf / Egr ???

I'll plug Carly in though don't think I'll get error codes, does that mean my thoughts are imaginary? Anyone experience similar ?

Carly showed no faults.....

Very hard to say - you as the regular driver are in the best position to tell. Have you ever felt it didn't do this in the past? If not I'm tempted to say its imaginary.

I recall that these gearboxes are supposed to "learn" and adapt to our driving style. Maybe its worth resetting that to see if it makes a difference?

Can't say I've noticed previously
It's a funny trait, the car will bumble along in 8th gear, a bit of right foot and it's nothing, (hesitience, vibration) nothing then it drops down to 7th and takes off.
I have played with the car and can replicate in the manual box, though it only seems to do it in 8th gear, so it may be driven below the torque curve


This morning I reset the adaptions, though believe it's only the throttle adaption, I'll take it for a run later,

There may be a glimmer of hope with a suggestion of vacuum pipes perished or cracked, so if there's no change I may end up pull the airbox and checking the pipes.

Whilst I could book in, I think it'd be pointless as Two code readers bring no error codes and it's one of those hard to describe faults but easy to replicate....