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If there's something that talks about an overhaul time frame I've never heard about it. The engine is essentially a scooter engine out of one of BMW's scooters. I've never seen literature in the workbook for the i3 about a so called overhaul interval.

From the literature of the i3 work book, the engine will kick on occasionally at 6.5%, and then turn on constantly at 3.5%. So you'd actually be running it at 3.5% "consumer" charge, so about 21% total charge.

By all means use the car however you want, I myself am curious to see how it holds up under constant driving conditions like you're talking about.
 
Per the BMW University training, IF you get to 4.9% or lower (relative, not counting the 10% held in reserve where the vehicle will stop - zero range indicated), you will not be able to use full power and will lose heating and a/c. The REx can maintain SOC (state of charge) from when it turns on in 'normal' use (but who determines what that is? - you!), but in North America, that's not all that much above the 4.9% where it then starts to restrict operations. IF you aren't pressing hard, or in a situation where it has a high load (could be cold and you need the heaters, the wipers, and are climbing the hill to get home)...it will start to disappoint you. If you can keep the charge above that point, you will not notice anything changing except the REx running (if at all). Even in other markets, where you can turn the REx on earlier, if you're really pressing hard, you could get to that point where your battery charge gets below 4.9%, and you'll probably notice things happening that are not normal. The i3 cannot handle long-term Autobahn speeds until you've exhausted the REx and the batteries, even if you stop to refuel frequently, and wouldn't be the greatest trying to take a trip through the mountains (although you could regain a lot of power going down!).

Only if you understand the limitations and agree with the design is the i3 a good choice. In my case, for what I have and plan to use it for, it's great. Your results may differ. I really believe BMW added the REx as a crutch to help people overcome the range anxiety of only having the batteries, unaided. If you regularly take trips greater than the battery range, at some point, you are going to be caught when you miscalculate, even with the REx. The difference is that you can recover if someone brings you a can of fuel...someone bringing you a generator isn't anywhere near as likely to happen to get you going again. If you're moving along at high speed or climbing a long grade, you may only get a mile or two in NA after the REx comes on before you reach 4.9%, and things start to slow down. You'll be able to go a lot further before that happens in other markets, but it can still easily happen if your trip is long enough or the route has long grades, or you're pressing your speed.

The i3 is NOT like an ICE, where you can go full tilt until you run out of fuel, or refuel when running on fumes, REx or not. It starts to shut down when you're getting to the end, and you'll notice!
 
Understood, and let's put some numbers to that. In my somewhat informal testing over 2 days, I found that if I drove no faster than 110 kph (113 kph as indicated on the dashboard), the Rex was keeping the SOC. Anything faster and I would drain the battery - definitely I couldn't drive at 120 kph actual for sustained periods.

This was on flat highway, with only me the car (180lbs), and about 16C, so no AC and no heat.

I do plan on long distance (800km) drives with a custom fuel tank in the front (which will hold enough for 4 refills).

I just hope the REx doesn't overheat. Thoughts?
 
jadnashuanh said:
The i3 is NOT like an ICE, where you can go full tilt until you run out of fuel, or refuel when running on fumes, REx or not. It starts to shut down when you're getting to the end, and you'll notice!
That's fine. I wasn't ready to go pure BEV, but I wanted something with as small an ICE as possible. I felt the Volt's engine was overkill. I'm hoping the i3 REX has properly hit the sweet spot between more ICE than you really need and too little to perform reasonably; that Goldilocks just right zone. I'm willing to accept some mild restrictions while using gas, in fact I prefer that the electric outperforms the ICE. It like it being biased towards electricity.

I am annoyed that we can't switch the REX on early in the US. With that capability and the right planning you could drive along at 25% beyond the REX capability for quite some time by drawing down from most of the battery. With only a few percent of the battery available as a buffer the exact sizing of the REX is much more important.

I'm torn between two conflicting urges: see how long I can go with my brand new i3 without resorting to using gas, or drain the battery as soon as possible and find out firsthand how the REX performs and what its limitations are.
 
jadnashuanh said:
Per the BMW University training, IF you get to 4.9% or lower (relative, not counting the 10% held in reserve where the vehicle will stop - zero range indicated), you will not be able to use full power and will lose heating and a/c. The REx can maintain SOC (state of charge) from when it turns on in 'normal' use (but who determines what that is? - you!), but in North America, that's not all that much above the 4.9% where it then starts to restrict operations.

The 4.9% threshold for restricted operation applies to the i3 BEV. For the REx the threshold is 1.9%. This is from sections BMW University I01 High-voltage Components chapter 13. Operating Strategy.
 
For what it's worth, here is our experience (i3 REx) so far. There are really two subjects in this thread: the CEL, and driving longer distances with the REx.

Re the CEL: ours came on within a couple days of delivery. It's been on constantly ever since. Today is August 8 and we took delivery on June 3. A couple weeks ago, BMW NA called to say that the CEL-related software update was ready and we should schedule an appointment with our dealer. I called the dealer immediately, told them the purpose of the service visit, and made an appointment for a couple days later. When I arrived at the dealer, the service manager said they had not received the software update from BMW NA and couldn't work on my car yet. I was told to wait for the dealership to call me. Still waiting.

Re driving longer distances with the REx: Every two weeks, we need a car for a 200-mile one-day round trip to a local farm to pick up a load of various produce. We bought the i3 thinking we would try using it for that trip, but could always use our other (ICE) car instead. The i3 has made four such trips. Driving at 65 MPH, outside temp. around 100 degrees F., the REx engine comes on at 72 to 75 miles, and runs the rest of the trip. At about 145 miles, I refill the REx fuel tank. The car performs entirely normally after the REx comes on--no impact on power, acceleration or anything else other than the slight noise of the REx humming away at the back. (Originally, I couldn't detect the REx at highway speeds, but after having the car for awhile, I can sometimes detect a slight vibration even at highway speeds. Not a big deal at all, just not quite as silky smooth as when running on battery.)

More as an academic than a practical matter, I was intrigued by the question of just what is a proper and an improper use of the REx. Could I, for example, drive the car 600 miles in a day with no chance to fast-charge along the way (let's assume I'm going on vacation to a place that distance away and I want to have my i3 for use when I'm there)? Would I risk damaging my car in some way if I did that, running the REx engine continuously for the vast majority of the drive?

So I had a conversation with the Genius guy at the dealership. I reminded him that we obviously didn't buy the i3 thinking we were getting a road-trip car, but what about the 600-mile-away vacation destination scenario. I told him I'm familiar with the BMW scooter that the REx engine comes from (just from reading reviews, although I also ride a BMW motorcycle), and that you could hop on the BMW C 650 GT and ride all day. So the REx engine should be capable of running all day, right?

He pulled out some info about the overheat protection built into the REx engine and said that under high-demand circumstances, high engine heat could result in power being curtailed. I answered that I hadn't encountered that and that situation was not what I was asking about. He agreed to investigate.

A day or so later, he called to say the answer he got from BMW was that the REx engine is not intended to be the "primary energy source". Duh! My follow-up question was: over what period of time? That is, of course it's not intended as the primary energy source over the life of the car. Not even so for a month or a week. But what about a day? Answer: "that's all I was told. Not intended as the primary source." I really could have figured that out on my own!

So I 'm still in the dark on the issue of extended or extensive REx operation. Other than our twice-monthly 200-mile round trips, the REx never comes on, and even on the 200-mile trips, we only refill the tank once. So I'm confident we're not violating the "not the primary energy source" advice. But it would be nice, someday, to get a more complete or helpful answer to questions such as these--what is the outer limit of the REx's capabilities? Under what circumstances do we risk damaging the car, shortening its life or increasing the chance of requiring major repairs?
 
I asked this question of BMW Uk and show an extract of their reply.

Thank you for your email dated October 22, 2013.
I will contact Cooper Croydon on your behalf and arrange for them to contact you regarding a test drive once they become available.

Regarding your question on the range extender, it will not recharge the battery but it will maintain the charge at a constant and allow you to carry on travelling. All you would have to do to carry on travelling is add more fuel when it runs out. You would however, have to use a fixed charge point to be able to recharge the battery to full again. I would have to point out that the BMW i3 was designed as a full electric car and using the range extender continuously would not be maximising the vehicles efficiency.
 
WHen the REx is running, you're getting in the order of 45mpg or so. The EPA's assessment of the i3 running solely on the battery with no REx operation, is rated at 124mpgE. So, depending on whether you could ever recharge the batteries on a longer trip, there are a bunch of ICE vehicles that could beat the i3 if you go longer distances and can't recharge the batteries - and, won't run into the issue of potentially running at a decreased output if you had to climb a long grade or needed the headlights, heater, etc. during that time. If you can accept those limitations, running on the REx can be done. Typically, that type of engine needs servicing more often than a typical ICE, and that may play into the overall cost of ownership as much or more than the cost of the fuel to move it.
 
jadnashuanh said:
... there are a bunch of ICE vehicles that could beat the i3 if you go longer distances and can't recharge the batteries - and, won't run into the issue of potentially running at a decreased output if you had to climb a long grade or needed the headlights, heater, etc. during that time.
Quite true. But not a single one of them exceeds 13 miles of EPA electric range. The i3 REx is a pure electric vehicle with no limitations and equivalent or better performance than all of them up to 72 miles of electric range, then some reasonable nods to laws of physics beyond that range.
 
CEL back on AFTER software update: On our i3 REx (delivered June 3), the CEL came on within a couple days of delivery. The software update was installed by the dealer on August 18. Right after that, we left town for a few days and didn't drive the car. Four days after returning and driving the car only a handful of miles each day (with the exception of one day when the car went about 200 miles (not the day the CEL came back on)), the light is back on as of yesterday. Has anyone else had this problem?

I believe there's a separate thread on our second issue, but we continue to get slow charging times. For example, just today I plugged the car in with a 50% SOC, and the dashboard readout reported an estimated 3.5 hours or so to full charge. That's the amount of time it's supposed to take from empty. Before the software update, I measured the current draw from the EVSE at 14.2 amps. I believe it should be closer to 30 amps (i3 Wallbox, maximum amperage claimed to be 32 amps). What's up?
 
There's another s/w update that refines the same things that you may need. While I don't' have a REx, it applies to the BEV as well. I got a call from BMW earlier this week informing me that I should make an appointment to have it installed, and I have an appointment next week to have it done. It also changes the logic that keeps the 12vdc battery charged (this runs the on-board displays and modules for 'normal' car functions).

They did two things with regards to recharging the vehicle...they tied the recharge rate to temperature, and limited the max amount - I would expect that AZ would be affected by that high temperature issue. That should be resolved by the end of the year, but will be a fact of life in the interim.

As to the CEL, can't say, but the latest s/w does also address some REx things again.
 
My CEL just came on for the first time today. I got my Rex a few weeks ago. I got a call from BMW telling me to come in for a software update the week before last, but when I took it in they discovered that I already had the most recent software version. I did use the gas engine for the first time over the holiday weekend, it seemed to work just fine. The onboard computer says all systems are OK.
 
My CEL came on today. My car is about 2 weeks old. About a week ago, I visited the dealer and had them read my key. The printout they gave me had a section called Dynamic Vehicle data which listed the Engine oil status as minimum. I wondered at the time if that meant the Rex oil level was low but didn't ask them about it. Since then, I've coded the car to enable Rex hold mode. I tried it a few times and it seemed to work fine with now errors. Then tonight, driving home, I was about 2 miles short on range and when Rex came on, so did the light. I guess I'll take it back in and see if it's logged a code.
 
I thought I'd post a follow up. I took the car in and the CEL was for a misfire on cylinder 1. The tech ran the Rex for about 15 min and when it didn't repro, cleared the fault and chalked it up to bad gas and a cold, sluggish engine. Well, the light came back on 2 days later. This time, they've had the car for 3 days and expect to have it 2 more.. They said that the tech was working closely with BMW in Germany because the tests he was supposed to run weren't working. Today, they said they are replacing the spark plugs, wires, coils, and intake manifold gaskets. The parts are being overnighted and the car will be ready Friday. I guess we'll see.
 
I bought my BMW i3 on May 28 at Hudson Valley BMW in New York. I absolutely love the vehicle and have no complaints about it as it runs great, but I do have a complaint about getting this faulty check engine issue fixed. Note, though I have the REx, I have never had to use it and it has come on for maintenance only twice. In the last visit to the shop they replaced the gas for me and also put in a good stabilizer.

The check engine light came on during the summer in August, two months after I bought the vehicle, for no apparent reason. At BMW Hudson Valley it took four days for the service dept. to resolve this issue through a software update. It seems that they have to wait for engineers in Germany to remote into the vehicle to do the software updates manually.
The same exact engine light issue apparently happened around November 30 or December 1, 2014. This time I was told that there was another software update needed and also a pressure valve related to the gas Rex engine needed to be replaced. Again they had the vehicle for four days. The day after I got the vehicle back that engine light came on again. It remains on days later and currently. I called around to a few more dealers and found one that has dealt with the CEL in the REx several times so am scheduled to bring it in on the 29th.

Another issue has come about ever since the last software update, which may or may not be the cause. The iPhone app will no longer pre-condition my vehicle and every time I've tried (which is about 20 times so far) it has not been able to do it. I have tried to issue the command from two different iPhones and it still has the same error message in the app about not being able to issue the command to the vehicle and in fact it won't issue any commands remotely to the vehicle now. Something got hosed with the communications link to the vehicle. Anyone else see this after the latest update?
 
IF the data sent to your phone is constant, i.e., it never updates things like the odometer or current battery charge. First thing is to ask them to perform an account reset, but if that doesn't work, my limited experience is pull fuse F115 and reinstall. Do this with the car off and no charging cable attached. This removes power from the telemetrics unit and forces it into a hard reset (that fuse may power a few other things, so you do need to have the car off when you do this to prevent other issues). Try at your own risk.
 
jadnashuanh said:
IF the data sent to your phone is constant, i.e., it never updates things like the odometer or current battery charge. First thing is to ask them to perform an account reset, but if that doesn't work, my limited experience is pull fuse F115 and reinstall. Do this with the car off and no charging cable attached. This removes power from the telemetrics unit and forces it into a hard reset (that fuse may power a few other things, so you do need to have the car off when you do this to prevent other issues). Try at your own risk.

It is not sending or receiving so the app is stuck in the past. I have a case open with BMW i3 Concierge Services. They said it could take several days to get the right people to reset the account. I tried resetting the F115 fuse as you suggested but that did not help. Must be a back end server issue.
Thanks
 
CompuMagic said:
jadnashuanh said:
IF the data sent to your phone is constant, i.e., it never updates things like the odometer or current battery charge. First thing is to ask them to perform an account reset, but if that doesn't work, my limited experience is pull fuse F115 and reinstall. Do this with the car off and no charging cable attached. This removes power from the telemetrics unit and forces it into a hard reset (that fuse may power a few other things, so you do need to have the car off when you do this to prevent other issues). Try at your own risk.

It is not sending or receiving so the app is stuck in the past. I have a case open with BMW i3 Concierge Services. They said it could take several days to get the right people to reset the account. I tried resetting the F115 fuse as you suggested but that did not help. Must be a back end server issue.
Thanks


Update- I had said it was not working above about 2 minutes after doing the fuse reset. Turns out that 10 minutes later after driving, it is working again. It's also worth noting that while it was not working neither was the GPS or the online BMW apps. I talked to Bryce who was helping me and he told me that my account was reset yesterday. I have the feeling that the fuse might've actually done the trick now.
 
It takes a few minutes for the module to reboot (think starting your smartphone) then to find a signal, then to communicate with the servers. To get the problem logged...and the likely 'fix', you should let them know so that there's at least another person reporting the problem so they can log it as a problem/solution and maybe figure out why it happens at all. Upon resetting my account (they did it probably 3 times over a 10-day period), none of them resolved my issue - the app data would go blank indicating nothing on the server, then the car would report the same old data - never changing. Seems in your case, the module was not communicating at all. Sounds like there may be more than one way for them to 'lockup', and thus, maybe more than one problem. As soon as mine was reset, the data sent to the server and then to my phone was up-to-date and correct.

It is more than possible that that fuse powers multiple modules. They advised not removing it, but given a few minutes, everything should be back to normal. A GPS also takes a bit of time to reacquire position especially if it lost that prior location information if it, also, was turned off by removing the fuse.
 
Rule One - only use ethanol free gas in your I3 - this fuel is just sitting there most of the time and you only want "Real" gasoline in the tank!
 
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