Acceleration at higher speeds

[fshuk1]

Driving Normal mode on the motorways, I find trying to increase my speed from 65 to say 70 or 75 is very slow. In fact sometimes I feel it is not going to make it and then I see oh it has, so it must be slowly.

At low speeds the acceleration is very very good. Exciting even.

I was under the impression that the acceleration is constant until max speed.

I just like to hear what your experience has been.

 

[Diggsy]

Watch your power percentage when that happens. If it’s not showing 100%, then you may have the loss of power issue (restricted speed) that others have seen.

 

[PristDean]

Driving Normal mode on the motorways, I find trying to increase my speed from 65 to say 70 or 75 is very slow. In fact sometimes I feel it is not going to make it and then I see oh it has, so it must be slowly.

At low speeds the acceleration is very very good. Exciting even.

I was under the impression that the acceleration is constant until max speed.

I just like to hear what your experience has been.

I think you have a problem there which your dealer needs to be aware of. I have no issue with high end acceleration at all

 

[Themist0]

Mine accelerates quickly at any speed ….60 to 70 plus to get past motorway traffic is a breeze

 

[Rolfe]

When I have driven on the motorway I have not been conscious of a lack of acceleration, and indeed one day I looked down to see the number 92 on the driver's screen. I resolved to set the ACC on the motorway to avoid doing that again. I wasn't flooring it though, because I wasn't in a hurry - it just sort of crept up to that as I moved with the traffic, without me actually having tried to get to that speed.

More relevant is an experience I had on a long straight stretch of single carriageway road earlier this month. I pulled out to overtake a slower car, and the MG4 shot ahead in its usual nippy manner. I saw another slowcoach ahead of the first one and decided to overtake it too. I was already going pretty fast, but asked for a bit more. At that point I noticed that the car didn't quite have what my late lamented GTi had in the same circumstances. But this is a comparison with a GTi, for goodness sake. In terms of completing the manoeuvre there was enough power there and it wasn't an issue. I wouldn't have described the acceleration as very slow, and there was no sense that I wasn't going to make it.

It's just possible that this might be a relatively minor manifestation of the power loss issue discussed in another thread, as Diggsy suggested. Bowfer thought his problem was worse in cold weather, so if it is that, it might deteriorate. We've also had a new member with what sounds like the same issue in a January 2023 car.

Is yours an SE SR? That seems to be the model the problem has manifested in.

 

[MartinSEsr]

Hi. What mode were you in? If normal or sport you should get significant acceleration. Eco applies a boring lack of response to everything including the brakes.

 

[Buster72]

Mine accelerates quickly at any speed ….60 to 70 plus to get past motorway traffic is a breeze

Exactly the same here. In fact the car is so quiet and smooth on the motorway that I have to keep checking on the speed. And the acceleration from 60 to about 80 is excellent.

 

[PristDean]

Hi. What mode were you in? If normal or sport you should get significant acceleration. Eco applies a boring lack of response to everything including the brakes.

Indeed, I tried out ECO for the first time in earnest yesterday and while it increased my miles p/Kwh I found it made everything feel a bit 'woolly' including the brakes which I had to press harder when needed. Bit puzzled that ECO changes the brake force required, feels like it introduces a bit of a safety concern, what's the benefit ?

 

[Buster72]

When I have driven on the motorway I have not been conscious of a lack of acceleration, and indeed one day I looked down to see the number 92 on the driver's screen. I resolved to set the ACC on the motorway to avoid doing that again. I wasn't flooring it though, because I wasn't in a hurry - it just sort of crept up to that as I moved with the traffic, without me actually having tried to get to that speed.

More relevant is an experience I had on a long straight stretch of single carriageway road earlier this month. I pulled out to overtake a slower car, and the MG4 shot ahead in its usual nippy manner. I saw another slowcoach ahead of the first one and decided to overtake it too. I was already going pretty fast, but asked for a bit more. At that point I noticed that the car didn't quite have what my late lamented GTi had in the same circumstances. But this is a comparison with a GTi, for goodness sake. In terms of completing the manoeuvre there was enough power there and it wasn't an issue. I wouldn't have described the acceleration as very slow, and there was no sense that I wasn't going to make it.

It's just possible that this might be a relatively minor manifestation of the power loss issue discussed in another thread, as Diggsy suggested. Bowfer thought his problem was worse in cold weather, so if it is that, it might deteriorate. We've also had a new member with what sounds like the same issue in a January 2023 car.

Is yours an SE SR? That seems to be the model the problem has manifested in.

No. Mine is an SE SR and I certainly don't have any such problems. I always drive in Normal and currently am getting 4.7 miles/kwh without having to try to drive any different.

 

[fshuk1]

So Today I was driving in a slip road, then joined a dual carriage and tried to accelerate. I got a message that I forget now what the exact wording was but it said that the power is reduced and I got this yellow exclamation light up. Anyone else got this?

 

[Rolfe]

That's showing the turtle. It's telling you it is restricting power because you are low on battery. But you are not low on battery. Something wrong here.

So far as I remember the people with the restricted speed problem (which it seems may have been fixed by a software update) did not see the turtle when it happened. Which suggests you have a different problem. Your car thinks the battery is about to run out, but it's on 22%. Does not compute!

How much further did you get? I mean, you didn't actually run out, did you?

When did you last let your battery balance at 100%, and how often do you do that?

 

[fshuk1]

The signs all went away after a few minutes. It seems it thought my motor was overheating for some reason. I am at 15% now with no problems.

I have an OHME charger that I charge the car to 100%. Not sure if OHME balances the pack or stops at 100% charge. May be someone else can tell me.

This is the message I got

 

[Rolfe]

The signs all went away after a few minutes. It seems it thought my motor was overheating for some reason. I am at 15% now with no problems.

I have an OHME charger that I charge the car to 100%. Not sure if OHME balances the pack or stops at 100% charge. May be someone else can tell me.

I'm pretty sure it balances the pack, so I shouldn't think there's a problem there. (If the SR isn't balanced frequently it seems to have a tendency to mis-report the remaining rage.)

View attachment 19508

This is the message I got

Hmmm, looks like you could be right. I've never had this happen to me, and I don't remember reading that in the manual. (Obviously I did read it, but it didn't stick.)

Maybe it's nothing to worry about, just the car reacting normally to overheating. If it keeps happening though, I'd tell your dealer about it.

 

[Eber]

So Today I was driving in a slip road, then joined a dual carriage and tried to accelerate. I got a message that I forget now what the exact wording was but it said that the power is reduced and I got this yellow exclamation light up. Anyone else got this?

Assuming it's not super hot in the UK and you were not driving on a race track before there should be no heat issue in this situation. I'd suggest to report this to your dealership.

 

[Pebble]

As a first stop, I'd look at the coolant level just to rule out a cooling problem.

 

[tsedge]

There are lots of reasons it could enter snail mode: overheating (motor or battery), lack of battery balancing (needs to keep charging after 100% for as long as it wants to balance), bugs.

Getting the dealer to have a look and see if they can read the problem from the fault codes is a good idea.