Acceleration Response 'Mk1 versus Mk2'

Yandards

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Replaced my 'Mk 1' Trophy (no rear wiper etc) car with a 'Mk 2' that has the rear wiper, one pedal drive etc a few months back but on a longer trip yesterday identified some odd behaviour regarding throttle pedal response.

On slowing down on approach to various roundabouts and seeing I could continue without coming to a stop there is a very definite delay between the increase power request from the throttle pedal to the car responding and accelerating. Tried this in ECO, NORMAL and SPORT modes and it was the same in every mode. It's also not a steering angle sensor limiting power (it's meant to do that) as it does the same thing on a straight section of road.

Don't recall the Mk 1 being this slow to transition from charging deceleration to acceleration and its something I would have noticed having done 20k in it!

It's around 2 seconds before the car starts to accelerate - anyone else who has driven both noticed this behaviour?

Was quite enjoying the 1 pedal drive mode but it seems to pull higher levels of battery power when stopped (8% in one case!) and even with the autohold applied compared to not using it all where the car power % shows 0. Whilst I appreciate it means the motor is ready to accelerate straight away it's not very efficient in stop start traffic compared to manual driving.
 
2 secs seems quite long.
I have the similar trophy and I too feel a lag, but not more than a quarter of a sec is my estimation
 
Tbh not noticed it in normal, don't use eco but find it very noticeable in Sport mode
Just assumed they were all like it
 
2 secs seems quite long.
I have the similar trophy and I too feel a lag, but not more than a quarter of a sec is my estimation
Once I noticed it I started more testing, ie the different modes as I was in ECO at the time. I know the steering wheel angle can also limit power delivery as part of the stability control system so wanted to rule that out too.

It was long enough that I was able to keep feeding in throttle before it responded. Ironically it doesn't seem to do this when in 1 pedal drive mode so it's clearly software side.

That transition is fairly harsh on the power control hardware, my PV inverter has a noticeable lag when switching from charging to discharging battery support so perhaps MG were seeing something in the data from early cars that made them tweak the code a bit.
 
Somewhat related, but on the deceleration side.

I noticed after the latest upgrade on my Trophy (has the rear wiper), that when coming to an intersection the regen braking is completely changed.

Previously it was stronger, just borderline agressive for the passengers, but it was continuous down to 5km\h, so when i needed to stop, or even brake just a tad harder, i would only feather the brakes and the car would respond immidiatelly.

Now, it feels like there is some change in when the car thinks it will benefit from the regen, so if i am already going slow or slightly decerating and need to brake harder, for the first travel of the brake pedal, the car does nothing. Since i was used to the car applying more regen i never had to press rhe brake pedal 'a lot'. I did check the manual and the current version does say there is a dead travel. I wonder if the manual in the car knows i am on another version and is updated? Has anyone an older manual for the Trophy in the car?

Now i find myself having to emergency brake a lot, since i fether the brakes, regen does not even happen, i pres a bit more, nothing happens and then if i have to stop i end up running out of road, so i press harder and harder more out of fear than controlled, to where the car figures out it needs to drop the anker.

I tested at all kinds of battery levels, and it's not like the Renault Zoe which if i set the limit to 80% and i am at 80% it would obay the limit and not regen. But feels exactly like that car at 80% or 100% (charge limited).
 
Somewhat related, but on the deceleration side.

I noticed after the latest upgrade on my Trophy (has the rear wiper), that when coming to an intersection the regen braking is completely changed.

Previously it was stronger, just borderline agressive for the passengers, but it was continuous down to 5km\h, so when i needed to stop, or even brake just a tad harder, i would only feather the brakes and the car would respond immidiatelly.

Now, it feels like there is some change in when the car thinks it will benefit from the regen, so if i am already going slow or slightly decerating and need to brake harder, for the first travel of the brake pedal, the car does nothing. Since i was used to the car applying more regen i never had to press rhe brake pedal 'a lot'. I did check the manual and the current version does say there is a dead travel. I wonder if the manual in the car knows i am on another version and is updated? Has anyone an older manual for the Trophy in the car?

Now i find myself having to emergency brake a lot, since i fether the brakes, regen does not even happen, i pres a bit more, nothing happens and then if i have to stop i end up running out of road, so i press harder and harder more out of fear than controlled, to where the car figures out it needs to drop the anker.

I tested at all kinds of battery levels, and it's not like the Renault Zoe which if i set the limit to 80% and i am at 80% it would obay the limit and not regen. But feels exactly like that car at 80% or 100% (charge limited).
I have that sort of behaviour on both cars but only when the battery is fully charged to 100% and it soon stops. Usually run the car in ECO mode as default but have also been using the 1 pedal (which isn't available above 90% SoC or so).

It's odd they keep messing with it as the car can clearly behave in a different way, ie the 1 pedal mode.
 
Was quite enjoying the 1 pedal drive mode but it seems to pull higher levels of battery power when stopped (8% in one case!)
That sounds like similar behaviour to mine. When stopped I've seen various power levels reported, both positive and negative.

Obviously a continuous negative power when stopped is nonsense, and after watching it change more closely as I came to a stop, decided it simply doesn't update the display when stopped. So any lag in the power measurement results in the eventual zero power never being shown 🙄.

Pressing the brake, parking brake or accelerator a small amount will probably update the display to 0.
 
That sounds like similar behaviour to mine. When stopped I've seen various power levels reported, both positive and negative.

Obviously a continuous negative power when stopped is nonsense, and after watching it change more closely as I came to a stop, decided it simply doesn't update the display when stopped. So any lag in the power measurement results in the eventual zero power never being shown 🙄.

Pressing the brake, parking brake or accelerator a small amount will probably update the display to 0.
Not seen any negative numbers!

There is an audible clunk from the back axle after a period of time - this is also when the motor stops working as a parking brake and the power drain drops a bit.

Autohold indication goes green prior to this though and even if I manually apply it the car still uses the motor as a brake.
 
Mine does that. When I'm pulling up to a junction, if I let the car come to a halt it won't move again for at least a second. It was quite disconcerting the first time it happened but I'm used to it now. No other car I've ever had does this, it's odd. Almost as if someone misplaced a decimal point when programming the thing...
 

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