MGS5 didn’t accelerate in uphill slope

[deetha54]

Hi everyone. 2 days back while I was driving my MGS5 uphill in a real slope when I had to stop and hold for another car coming downwards. Then when I started to climb again, the car didn’t respond at all . Then I changed mode to SPORT and again pressed the accelerator full but the car moved very very slow for another 10 seconds or so….. after that the car responded fully again. The power consumption also didn’t exceed 50% during the incident.
Regenerative braking was set to LOW
AC was OFF , not overloaded and I have driven the car many times earlier in worse slopes without any problem
Iam really anxious to take it to similar uphill slopes due to this incident. Anything on this which I could have done or could do??

 

[Alb]

What was your SOC at the time?
Also, any chance the motor was overheating?

 

[T1 Terry]

I was caught a few times like that, it was me trying to do a heel & toe start on a hill, there is no throttle response when you have your foot on the brake ....
Hard to learn how to use the electric park brake and how to get it to release at the right time .... applied the electric park brake to stop rollback, then you can keep your feet away from the brake pedal ..... learning to trust that the car will stay put just by flicking toggle switch takes a bit of relearning ..... but once you master it, you really wonder why all cars don't work like that .....

T1 Terry

 

[5teep]

I'm thinking the car 'should' auto hold on hills, if it doesn't then use the handbrake for sure rather than rely on the foot brake.

 

[deetha54]

What was your SOC at the time?
Also, any chance the motor was overheating?

SOC must be somewhere around 70%….. And motor overheating… Iam not sure How I would come to know about that.

 

[Jazzyboy]

I had a very strange experience last weekend. I park on a slight driveway slope and put the car in drive mode and removed foot off brake but then rolled back! That was a shock as it's never done that before. I tried to recreate the issue and discovered that the drivers door was not fully closed and the car rolled. If door is fully closed it won't roll. I'm thinking of getting some permanent chock blocks installed on the drive

 

[TimothyN]

Speaking as a lifelong aeroplane owner, bringing chocks into your life brings a whole world of unimagined pain.

 

[Ian Key]

I had a very strange experience last weekend. I park on a slight driveway slope and put the car in drive mode and removed foot off brake but then rolled back! That was a shock as it's never done that before. I tried to recreate the issue and discovered that the drivers door was not fully closed and the car rolled. If door is fully closed it won't roll. I'm thinking of getting some permanent chock blocks installed on the drive

I haven't tried it but if you put the handbrake on after putting it into D and before removing your foot off the foot brake does that stop the car rolling back?

 

[tsedge]

My MG4 does this. I live on a very steep hill and occasionally when manoeuvring on it, I will get this situation when I press the accelerator and the car just sits there. I think it gets confused by the steepness and the power required to move off.

The remedy is simple. I now just always apply the parking brake so I am doing a hill start and the car is then fine and moves off properly.

I have never thought about this as a fault, just a characteristic.

 

[Jazzyboy]

I haven't tried it but if you put the handbrake on after putting it into D and before removing your foot off the foot brake does that stop the car rolling back?

To be honest I don't want to try it shouldn't be rolling

 

[hothotmilo]

My MG4 did that the other day. I didn’t know what to do so I had it towed and checked. They couldn’t find anything wrong.

Could you elaborate the remedy? What is parking brake? If you could give a step by step guide I’d really appreciate it.

 

[T1 Terry]

My MG4 did that the other day. I didn’t know what to do so I had it towed and checked. They couldn’t find anything wrong.

Could you elaborate the remedy? What is parking brake? If you could give a step by step guide I’d really appreciate it.

You can't have your foot on the brake and drive off with the throttle pressed at the same time, flicking the park brake switch holds the car from rolling backwards and can either be released as you start to apply the throttle, or it will eventually let you drive off when it figures out you didn't release the park brake and releases it for you.
took a while to get the head around that one, but you certainly can't do a brake job like you could do in the old ICE powered car

T1 Terry

 

[hothotmilo]

You can't have your foot on the brake and drive off with the throttle pressed at the same time, flicking the park brake switch holds the car from rolling backwards and can either be released as you start to apply the throttle, or it will eventually let you drive off when it figures out you didn't release the park brake and releases it for you.
took a while to get the head around that one, but you certainly can't do a brake job like you could do in the old ICE powered car

T1 Terry

I remember when I pressed the throttle I released the foot brake. So the throttle was the only pedal being pressed. But the car would not go forward, it was rolling backwards because of the slope.

So you mean I should apply park brake, then press throttle to move forward? And the car will release the park brake automatically?

 

[Alb]

So you mean I should apply park brake, then press throttle to move forward? And the car will release the park brake automatically?

Yes

 

[NikLiverpool]

Ok, this is from a very different car but may help.
Wife's BYD atto3, when autohold on has a massive lag when pressing the accelerator.
To the point of being dangerous when you try and move quickly into a roundabout.
Had to switch it off completely.
Latest update kinda improved it. Kinda..

 

[majorwedgy]

I had a very strange experience last weekend. I park on a slight driveway slope and put the car in drive mode and removed foot off brake but then rolled back! That was a shock as it's never done that before. I tried to recreate the issue and discovered that the drivers door was not fully closed and the car rolled. If door is fully closed it won't roll. I'm thinking of getting some permanent chock blocks installed on the drive

Had this exact situation myself, I thought it was because I got in and started driving too quickly, the brake disengaged but there was no drive! Squeaky bum moment as there isn't much space between our house and the car!

 

[T1 Terry]

Had this exact situation myself, I thought it was because I got in and started driving too quickly, the brake disengaged but there was no drive! Squeaky bum moment as there isn't much space between our house and the car!

That might possibly explain why my MG4 rolled forward on the trailer, even though it was in reverse with a bit of throttle applied, most inconvenient and required serious wood block staking to get the tyres on each side, high enough to roll back onto the tilt trailer platform ....

T1 Terry

 

[hothotmilo]

Hi Terry, thanks. I’ll give it a try. But I still don’t understand why when I fully released the foot brake and only apply the throttle the car still won’t move (it rolled backwards)..

 

[tsedge]

Yes

Yes - this is normal for steep slopes up or down (and when reversing too).

I live on a very steep hill and so I'm used to this behaviour.

Basically, if the road is steep and you don't apply the handbrake before moving off, there are circumstances when the car just won't move even if you push right down on the pedal. Not sure why this is, but the remedy is easy - always set the parking brake if manoeuvring on a steep slope and it will work properly.