Another new (and mostly happy) MG4 owner + tyre question

[enragedbadger]

I picked up a (new to me) 23-plate MG4 Trophy LR about a month ago, and so far I'm pretty pleased. (model year 22, no rear wiper).

The biggest annoyance so far is the TPMS keeps flagging up. Then I noticed the dealer (official MG dealer, mind!) fitted the wrong size tyres at the rear. As best I can tell, I'm supposed to have 215/50R17 and that's what I have in front. At the back though I have 215/55R17. I know it's not a massive difference but I wonder if it affects the TPMS (I assume its based off wheel rotation speed differentials?).

Also my efficiency is not great, averaging 2.5mi/kwh. Is that just my heavy foot?

Happy to see an active community here!

Ooh and one more q while I have your attention: the dealer gave me a new granny cable, but not a (I think it's called) type 2 AC cable? Should I pester them for one or just get one from (Amazon/Halfords)? I don't currently have a charge box at home - I first need to upgrade my decades old meter to a smart meter - so using public charing only for now.

 

[Jomarkh]

Hi and welcome to the forum.
Does the error show on the same wheel every time?

 

[ReintjeWA]

The tpms in the MG4 uses actual pressure sensors, so rotational speed won’t be an issue. It is most likely that the tyre pressures are close to the trigger value, and with temperature difference it flags on and off. Try pumping up the tyres some more and see if that fixes it.

 

[Jomarkh]

Ooh and one more q while I have your attention: the dealer gave me a new granny cable, but not a (I think it's called) type 2 AC cable? Should I pester them for one or just get one from (Amazon/Halfords)? I don't currently have a charge box at home - I first need to upgrade my decades old meter to a smart meter - so using public charing only for now.

The car was probably originally sold with just the granny. You could ask to swap it for a type2 32A but probably best just buy the one you want.

 

[ReintjeWA]

Ooh and one more q while I have your attention: the dealer gave me a new granny cable, but not a (I think it's called) type 2 AC cable? Should I pester them for one or just get one from (Amazon/Halfords)? I don't currently have a charge box at home - I first need to upgrade my decades old meter to a smart meter - so using public charing only for now.

You may need a type 2 cable for some public chargers, I would buy my own, the dealer would just give you what is cheapest for them to get.

You could mention the tyres to them, but again they’ll just put the cheapest tyres on they can find, so might be worth fixing yourself. Are the front and rear tyres the same brand/model?

 

[enragedbadger]

Thanks for the responses and the welcome!!

Does the error show on the same wheel every time?

Rear tyres only, usually the left first then the right.

The tpms in the MG4 uses actual pressure sensors, so rotational speed won’t be an issue. It is most likely that the tyre pressures are close to the trigger value, and with temperature difference it flags on and off. Try pumping up the tyres some more and see if that fixes it.

I've checked them with an electric Ring pump multiple times and they seem fine each time... I'm confident they're not actually low pressure.

You could mention the tyres to them, but again they’ll just put the cheapest tyres on they can find, so might be worth fixing yourself. Are the front and rear tyres the same brand/model?

No, different brands front and rear. Front is Continental PremiumContact, rear is something called RoadX RXMotion

It's this:

Yikes!

 

[salty]

To the forum. Doubt you'll get a free cable from the dealer, you've had the car for a month. But no harm in asking. Probably best to buy one. Although you'll probably never use it. As most chargers are tethered. Always handy to have both a Granny Charger and a Type 2. Then your covered for everything.

 

[siteguru]

I've never used my Type 2 cable ... I've often used my granny cable.

 

[ReintjeWA]

Thanks for the responses and the welcome!!


Rear tyres only, usually the left first then the right.


I've checked them with an electric Ring pump multiple times and they seem fine each time... I'm confident they're not actually low pressure.


No, different brands front and rear. Front is Continental PremiumContact, rear is something called RoadX RXMotion

It's this:

View attachment 40561


Yikes!

I think the continental is the factory fitted tyre.

What pressure are you running in the tyres? I’ve got mine set to 2.8 bar cold (they go up to 3.0 on a proper drive). I think the threshold for the alarm is 2.4 bar if I’m not mistaken.

 

[enragedbadger]

I think the continental is the factory fitted tyre.

What pressure are you running in the tyres? I’ve got mine set to 2.8 bar cold (they go up to 3.0 on a proper drive). I think the threshold for the alarm is 2.4 bar if I’m not mistaken.

whatever the sticker in the door says, I think 36psi which is 2.5 bar

 

[Gordon]

The first year I had my car the pressure alarm was always going off during the winter. Usually went off after a few miles. The pressures were never actually low. I learnt to ignore it. The second winter it never went off. I await this winter with interest.

 

[Gordon]

The first year I had my car the pressure alarm was always going off during the winter. Usually went off after a few miles. The pressures were never actually low. I learnt to ignore it. The second winter it never went off. I await this winter with interest.

 

[Rolfe]

My tyres were on 2.8 bar (warm) when I had the punctures on the Hardknott pass and I wondered if that contributed. I had become so sick of the bloody boing last October that I inflated them all to 2.6-2.7 cold, thinking that this would drop slowly over the winter anyway, but it didn't. Then in March/April on a rough but not insane road, three bloody punctures.

 

[dsimpkins]

I have the same model MG4 as you. I keep the tyres slightly higher than what they should be in winter to stop the annoying bongs. The TPMS seems very sensitive in cold weather.
215/50 R17 is the correct size tyre for your MG4. The 55s on the rear will have a slightly taller sidewall, but should be fine. Might help with efficiency by being slightly larger overall diameter.

2.5mi/kwh could be about right. Temperatures are getting lower, and efficiency is less in colder weather. If you are doing mostly short commuter journeys then it will effect efficiency. I get better efficency on way home from work, than on journey to work as it is warmer on way home. Efficiency on longer journeys should be better, and I can get about 3.8 this time of year on a long journey. IN the summer can easily get over 4, and 5 is achievable if light footed.

Other than a heavy foot, the other factors that effect efficiency are using the cabin heater, and also intelligent battery heating. Given your location in the UK I would suggest that if turned on, you turn off intelligent battery heating. Only really need it in sub zero temperatures.

Mine was supplied with a granny cable. Some people who bought their car via leasing company got both cables, but from MG you would normally only get granney cable. You can get a Type 2 to Type 2 (male to female) cable cheaper online. As you have a 22 model year SE LR then you benefit from 11kW onboard AC charging. In order to be able to get the fastest AC charging speeds you will want a 32amp 3 phase Type 2 cable. I bought a 5m cable, with a storage bag. 5m should be sufficient for most chargers. It's a thick cable, so longer cables will take up more room weigh more. Got mine from EV Extras after a recommendation from this forum. Here's a link:
Type 2 EV Cable Three Phase | 32AMP-Green or Black | 1.8 ,3 ,5 ,7.5 ,10, 15 Metres - 22kW

 

[enragedbadger]

@dsimpkins Thanks, that's useful.

Most trips are 1.5 mile school run, 4x a day. Probably not great for efficiency, but better than my other car (a diesel SUV).

Might try pump up the tires just a little extra, just enough to avoid the nagging!

Yeah I should turn off the battery heating, it's really not so cold here yet, morning are still 10+.

 

[dsimpkins]

So 2.5 for those short trips sounds about right. The intelligent battery heating made a significant difference to efficiency for me. In summer with longer trips you should see much better efficiency. The GOM goes over 300 miles per 100% charge for me.