u/VestKors_Maker

This is an update on a post I had about experiencing significant 1-2 second lag in take-off when I put my foot on the accelerator.

In short, the issue seems to have resolved itself in a very strange way. The car seems to have reset itself somehow.

I had my MG4 2026 Essence charging through the day yesterday. The charging was scheduled for when the solar panels of our house are typically generating power. I checked the MG iSmart app to see the SOC, but the app kept timing out and said that the vehicle was in "deep sleep" or something similar. I then went to the car and pressed the lock/unlock button on the driver side door (without the key) so the screen inside could activate and show me the SOC that way. I just wanted to see if the car was charging. First press of the button - nothing happened. I pressed again and the car started ticking and activating systems as if it was coming back to life/waking up. I could see the car was indeed charging, but thought it strange that it was in "deep sleep"

Today, I needed to take the car to the dealership for a full day of diagnostics. I unplugged the car, pulled out of the garage and drove off. Sure enough, the car had the same major lag issue as before. I tested this a couple more time at intersections of my suburb, and sure enough it was still there.

I had to wait for traffic to clear a bit before I could pull into one of the main roads going past my suburb. During that time, the trip data page reset itself. When I put my foot on the accelerator, the car took off almost instantly as it's supposed to. I had a few traffic lights to test the take off capabilities, and sure enough the car was behaving as it should with no issue.

I arrived at the dealership to explain the situation, but no-one there seemed to know I was booked in for today, even after me showing them the email details. Nevertheless, they got their lead technician to come out and have a look at the car. I explained what the issue was and that it seems to have resolved itself. Apparently, some cars can develop a temporary software error and the car can't clear the computer. They said that they can do it manually for me if it happens again and also check battery health etc. In short, they did not really have an answer and did not have a booking for me as I expected them to have. Since the car is fine now, and I at least have a paper trail of this issue, I decided to leave it as is.

I drove to work and also noticed the car being more energy efficient than when we first got it, with the ride being smoother. The percentage power applied is also a lot less now with acceleration than before. So, I am thinking some software issue caused some light braking to be applied at all times. Since the vehicle seems to have reset itself somehow, the issue is resolved.

This whole saga has left me confused and perplexed. My only hope is that this was a one-time issue and I don't have to go back to the dealership again until scheduled service time.

Has anyone experienced their car suddenly losing the ability to take off "normally" from stand still? As in, there is a 1-2 second delay before any movement of the car takes place.

I know it's a bit lengthy, but here's a bit of history if you require more context:

I recently bought an MG4 Essence 64 2026 model (new). Before the purchase, I test drove several other EVs (BYD, Volvo, Kia). During the test drive of the MG4, both my partner and I liked the vehicle and its smooth performance. I really liked how every EV, including the MG4, has near instant power and takes off really fast, especially when compared to an ICE.
The first week I've had it, the car was amazing. I would demonstrate the near instant acceleration form complete stop to friends and family who never had been in an EV before. To be clear; I don't drive like this all the time. My partner sometimes says I drive too relaxed. About a week after purchase, the car suddenly showed significant lag between when I put my foot on the accelerator and to when it started moving when completely stationary. This caught me off guard a few times, particularly when I'm taking off at traffic lights and trying to cross a busy road. I'm also not talking about a few milliseconds delay, but a good full 2 seconds. The car would also not give the full amount of torque after this, but sort of ease into acceleration as if it was in eco-mode. If I want to avoid this, I have to time things really well so I don't get honked at at lights or potentially cause an accident when trying to enter a roundabout.
It is literally like there is no power delivered to the motor, even though the on board display shows power applied ramping up very rapidly. I cycled through every driving mode, toggled every safety setting, charged the car to 100% to calibrate the BMS (as per manufacturer manual), I did a full factory reset of the infotainment set. I even tested this when the battery was cold (just started the car) and when I've been driving a while. I toggled the autohold function. I even toggled between one-pedal drive mode and normal drive mode with different regenerative settings.

I took it to the MG dealership I bought the car from for a quick initial diagnostic test, but have little hope they will be able to help. I'm scheduled in for a full day of diagnostics next week, but after an initial test drive by one of the service guys, they say the car drives as it should and there is nothing to worry about. He even tried gaslighting me in saying that all EVs are like this and is just something to get used to. I've been reading up on EVs for the last five years or so and know that this behaviour is not normal. I emailed the service manager to express my concerns and asked to get one of the service technicians to sit in the car with me to allow me to demonstrate the issue when I take the car in next week.

I've read of other issues people had where the car would not accelerate past a certain point, but nothing like this issue I'm facing.
Has anyone else experienced anything like this in their EV?