Hesitation when cruising

[robf]

I've noticed this on the commute this morning, but i think it was happening over the weekend.

On a steady commute doing about 70mph (so under 2,000rpm) the car would hestiate when applying throttle very briefly, as if there was an artificial limiter or the brakes were holding the car back. If i hadn't already done 10,000 miles, i would have suggested it was the cylinder deactiviation as it 'feels' like how i'd imagine deactivation being - a dull-wittted in hesitation in reacting.

Once the throat is cleared - and it a few milisconds - it feels absolutely normal. Any ideas?

[Markp]

Sounds like cylinder deactivation. Others describe it as feeling they have gone over small bump. But I occasionally get similar momentary hesitation.

[Leo-RS]

Sounds like the switch from 4 cylinder to 8 cylinder mode to me.

Switch over to your fuel consumption screen to see if it only happens when transitioning from 4-8 cylinders.

[robf]

I did put it on the efficiency screen - how do you actually know when it goes into 4cyl mode; is there a particular graphic?

[doodlebug]

Yep, the sliding MPG gauge goes green and it'll state 4-cylinder mode activated.

[robf]

Thanks - i'll watch it like a hawk tonight! It just seems odd that i havent noticed in up until now, 10,000 miles in...

[Bit_evl]

stay in comfort mode.
select the screen with the horizontal line for mpg.
coast on a very light throttle at 60-70mph.
below the line on the mpg it should display 4cyl mode enabled
open the throttle and it will go off.

[MikeFish]

4 cylinder mode works in comfort, dynamic and manual, the mode doesn't matter just stay on the throttle very lightly and you'll see the bar go green as described above. It's quite noticeable visually on the DIS when it happens.

[Bit_evl]

agreed, i have just found it easier to bring up in comfort mode.

[brab]

It's not on efficiency screen, it's on On-Board Computer / Consumption...

On my car I have never noticed COD switches in either direction, buttery smooth...

[robf]

Glad you mentioned that, as i thought i had a deeper issue with the car as it never showed 4cyl mode on the efficiency screen!

Following your instructions, the car actually goes into 4cyl mode a surprising amount of time. Curiously though, the last couple of days the hesitancy has gone away and i can not detect when the car switches cylinders. Wondering if i have bad fuel or something

[MikeFish]

As above, I sometimes have the DIS on just to see how much it switches between the 2 as I originally thought it wasn't working, but was surprised how much it does and I just don't notice it.
BTW Rob, I experienced something similar to your brake issue yesterday with my steels on cold and wet tyres. It felt more like a 4 wheel slide hence the ABS didn't kick in then suddenly one of the wheels gripped (I assume as it warmed) and the car suddenly started braking heavily. It was only a slow speed (less than 30mph) least than a minute after getting into the car and I didn't brake particularly hard. Maybe due to tyres more worn than before and colder temps