Easy activation of Range Extender

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Just wondered what happens if you use up all the available petrol. Does the car stop as I would expect so I imagine you would need to swap back to electric and make sure you have a bit in reserve so you can get to the next petrol station ?


B. C.

Harold Wood
UK
 
hey guys awesome tips, I am waiting on my new i3 2015 rex :D

Anyone knows a good electrical installer in LA area? What fast charger u guys got? Portable? Wall fixed? Jesla?

Thanks
Danny
 
bscurtis said:
Just wondered what happens if you use up all the available petrol. Does the car stop as I would expect so I imagine you would need to swap back to electric and make sure you have a bit in reserve so you can get to the next petrol station ?


B. C.

Harold Wood
UK
The car will turn on the REx at about a 6% SOC, if you haven't done it already. Depending on what the SOC is when it runs out of gas, is the same as not turning it on...you'll go until the computer reaches what it labels zero SOC, then stop. So, it's hard to say. Some people turn the REx on early, then continue on with what's left in the battery. When both are empty...you stop.
 
bscurtis said:
Just wondered what happens if you use up all the available petrol. Does the car stop as I would expect so I imagine you would need to swap back to electric and make sure you have a bit in reserve so you can get to the next petrol station ?

I have actually never experienced this situation, but it is fair to say that you're more likely to run low on electric first, meaning the REx will come on automatically with 6% SOC remaining.

On longer journeys, I usually engage the REx with about 20-25% SOC left. I've taken mine from England to Germany and NL twice now, using CCS and petrol top-ups without any problems.

There are a few things to keep in mind though: If the REx engine is started from cold, it goes through a about 5 min warm-up cycle, during which SOC can still slightly go down. Eventually, the engine will then rev higher and bring the battery SOC back to where the REx was engaged. Also, the speed you are travelling at has a great effect on the effectiveness of the REx. When SOC is low and the REx is warming up, then I usually drop speed down to 60 or 65 mph, while my normal motorway cruising speed is 65-70 mph.

Generally speaking - and to answer your question - you're more likely to find a working and functioning petrol station in most parts of the EU, but this obviously depends where precisely you live, because there are more remote parts. The REx can take you 60-75 miles depending on weather conditions and driving style (remember, the REx is only a 34bhp engine), which is plenty to make it to the next fill-up.

I have no range anxiety. I have "using-petrol-anxiety". :)
 
I'm still not sure what the situation would be in the following situation:-

Say I swap to the Rex at 75% state of charge as we can in UK/EU and I inadvertently run the petrol tank dry. Will I be able to manually re select going back to the battery by cancelling ' hold state of charge' ? I don't see why not and would the REX suffer from running its petrol tank dry. I know this is an unlikely situation but could just happen. I know its like using the battery as a range extender for the REX.

B.C.
UK
 
RExingIT said:
I've done the Eurospec coding on my i3 REx (thanks to DVD in Motion) and for easy access I marked it as a favorites button. I wanted to pass on this trick.

To do this, follow these steps.

1. Navigate to Menu/settings/ Range extender.
2. Hold down the favorites button that you want to use. I used 7. As usual, after a few seconds it will record your selection.

To activate the Range extender with your favorites button, push it twice in a row. First push brings up the list of favorites as usual, the second push less than a second or two later checks or un-checks the activation box on the range extender.

Nice and easy, saves all the time while on the road of trying to navigate to the specific menu. 2 pushes to turn it on, 2 pushes to turn it off.

Enjoy :D

So DVD in motion actually recode your whole system to Eurospec? I thought their process looks simpler as compared to the other company... maybe they just unlock it... Is there anyway we can keep US spec but just unlock the Range Extender function?
 
bscurtis said:
I'm still not sure what the situation would be in the following situation:-

Say I swap to the Rex at 75% state of charge as we can in UK/EU and I inadvertently run the petrol tank dry. Will I be able to manually re select going back to the battery by cancelling ' hold state of charge' ? I don't see why not and would the REX suffer from running its petrol tank dry. I know this is an unlikely situation but could just happen. I know its like using the battery as a range extender for the REX.

B.C.
UK

Hi B.C.,

yep, works like you guessed, with the exeption that you don't have to uncheck anything. The engine yust peters out, the checkbox unchecks all by itself, and you're on electrons only. The engine and fuel system is designed to deal with this situation perfectly. My guess: besides the advantage of being a pressurized system, the tank isn't actually totally empty when the gauge reads '---' and the engine stops (even in EU-spec).

Regards, Steven
 
epirali said:
WoodlandHills said:
I have it and I live in the U.S.

Yesterday I set off for the airport with less than 75% SOC, hit the REx button as soon as I turned the car on and drove on the REx 3/4 of the way there and back. The REx ran out of fuel about 5 miles from home and I plugged in with over 50% remaining. I only needed to use this strategy because we forgot to plug in the car the night before and normally we can get to LAX and back on a full charge.

Dvdinmotion was well worth the $150 for the peace of mind. We can just jump into the car no matter the SOC and drive where ever we want.....

Just want to say that for $20 more Code My Car (created another thread) can do this and a list of other options you may want.

How's that working for you? I am between Code My Card and DVD in Motion... CMC seems more value though. Just not sure about the warranty as my car is leased... Any thoughts on that will be highly appreciated.
 
bscurtis said:
Say I swap to the Rex at 75% state of charge as we can in UK/EU and I inadvertently run the petrol tank dry. Will I be able to manually re select going back to the battery by cancelling ' hold state of charge' ?
An i3 is always propelled by its battery pack, never by the REx engine directly, so there's no "going back to the battery" pack. If the REx engine is running, the battery pack's charge level won't drop as fast or at all. When the REx engine runs out of fuel and stops, the battery pack will continue propelling the car but with its charge level dropping faster than it did when the REx engine was running.
 
Enabling the REx to start earlier and recoding it to know it can use more of the tank is another thing. Both must be done to maximize your use, and I'm not sure people have discovered both (I have a BEV, so haven't looking into it further). FWIW, the actual tank is the same as used in the rest of the world, but the computer has been programmed to not use all of it for the USA...you have to overcome that 'feature' to let the car use it.
 
I went to DVD in motion road. It was so easy. Ordered it at midnight. In the morning, an email containing a small file was there since the middle of the night. Copied it to an USB key. Insert it in the car. Locked the doors the time to take a coffee and when i started it back, i had the option to but the REX in Hold Mode. It was so easy !

I will also surely try Codemycar one day.

Louis
 
Hi Steven,

Yes what you said makes sense and its nice to know if I run out of petrol in the fast lane of the motorway I won't suddenly find the regenerative breaking turns me into a sitting target.

I have done a few long runs about 200 miles approx.
On those occasions I started off fully charged and with the tank full. I selected 'hold state of charge' at about 75% charge and refilled the petrol tank on arrival. On the way back I used the battery until the REX took over which easily got me home and I recharged overnight in the garage.
It was much more straight forward than I thought it was going to be. and button number 7 makes it all so easy.
Thanks to one and all for the good advice.

B.C.
UK
 
Be careful not run the petrol tank dry as this could damage the small pump and filter in the tank.
 
Kiwi said:
Be careful not run the petrol tank dry as this could damage the small pump and filter in the tank.
FWIW, I don't think that the computer actually will let you run the tank dry...just like the stock US implementation, the tank is about 2.5g, but you can only use 1.9 before it shuts the engine off...I think there is a similar small amount left in the tank regardless - it's the computer turning it off, not it actually running out of fuel.
 
Kiwi said:
Be careful not run the petrol tank dry as this could damage the small pump and filter in the tank.

False.

Run it "dry" because "dry" is not dry. The car will shut down the REx (including the fuel pump) and continue on electric seamlessly, then fill up at the next station you encounter (if you are on a road trip). Works very well.
 
This is the reply I got from BMWi3 chat,


'I can confirm that the BMW i3 REx petrol motor performs exactly the same as a conventional vehicle, a strainer system and integrated fuel tank filter would prevent debris from entering the fuel system. We would never recommend allowing your vehicle to run out of petrol however I understand your concerns that you may damage the vehicle if this did happen.

I hope that this is helpful. If there’s anything else I can do for you please get in touch.'

They haven't said that the cars computer stops the fuel tank from running completely dry but I can well imagine the answer may have been a stock answer
 
Probably the same people that have told i3 owners that the car has run flat tires (it doesn't).

Riddle me this... In the US a non-coded car is only allowed to use 1.9gal of the 2.4 (or most likely slightly larger in true volume) and then the REx shuts off. To someone that doesn't know better they might think "OMG! I JUST RAN MY REx DRY! I HAVE RUINED THE FUEL PUMP! OMG!" But they haven't because the computer won't let them use the extra liter of fuel that is still in the tank.

Do you get it now? It's the same setup even if you are coded for 8L (2.4 gal) or live in a country where you have 8L from the factory, most likely the tank is at least 10% larger, so there is nearly another 1/4 of a gallon left in the tank, the pump will never run dry, the computer will not let it. Whomever you chatted with is just covering their own behind and most likely not intimately familiar with how the i3 works, possibly has never even driven one.

But go ahead and keep believing whatever you want, I'll keep doing exactly what I and many others have done with no damage and no problems.
 
On balance I agree with what you say but it is weird that the people who are supposed to know don't seem to.

When I bought my i3REX I asked the sales girl what happens if you run out of petrol but still have some charge left in the vehicle
and she simply said she didn't know. At least it was an honest answer.
I was also told by one of their engineers, specially trained to work on i3s, that if I use the range extender for several hundred miles the car would get slower and slower but this isn't what REX owners on here have experienced provided you keep a reasonable amount of charge in the battery as a reserve to help the REX if it is struggling up a long steep hill.
Its all good fun and I love my solar orange/frozen grey i3Rex. I figured that if I could charge at home from a domestic socket overnight I could do round trips up to 70 or 80 miles and the money I saved on petrol made buying petrol for long runs cheap so I never even bothered with being preped for DC rapid charging.
So far so good

BC
UK
 
The i3 is an all new vehicle for everyone at BMW. Or it was when it was released nearly 2 years ago. That said a learning curve and some misconceptions are to be expected. There was some training done but not everyone participated and not everyone that did participate probably paid attention to every detail or asked random questions like this one. It's the owners that are out driving the cars every day that really figure out and learn the intimate details of the car, its quirks and how it performs in certain situations.
 
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