BMW i3 FIRE

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Of course it’s always your choice, but I’d suggest more measured language when posting here. Nobody here that I know of works for BMW or is part of any dealer-industrial-complex :) IMHO sticking to facts and questions and avoiding extreme characterizations will get you the most info and prevent any future issues of people bringing up past posts in some adversarial/legal venue.
Excellent words
 
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So BMW UK report claims that the fire occurred due to a missing plastic oil cap.

We'll assume for a second that this is true.

The question I ask then is:
Does BMW i3 Rex have an oil pressure sensor? I cannot seem to find one in any technicical literature.

And if it does, does it have a red "oil" sign in the dashboard to indicate such locc of pressure/oil?

Perhaps those of you who got an I3 rEx may be able to help. I don't remember ever seeing one lightning up on the dash when turning on the car, as part of the dash lights check.

Why does BMW i3 not have an oil pressure sensor?

What is the Type approval underpinning the obligation to fit a vehicle with warning devices such as low or no oil pressure?

How come that no warning lights whatsoever showed up on dash?
 

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Could you provide some info on what happened to your car? Posts without any details can seem like fishing expeditions…
I was driving for 20-30 minutes when a guy behind me started honking and flashing his lights. when I looked in the mirror I saw smoke. I immediately pulled over. in the next 2 minuted the whole car was engulfed.

Although I have comprehensive cover, I don't believe in coincidences, and need to know what happened.


On initial inspection the fire appears to have started on the left side of the car, between the electric motor and the car shell.
However, a BMW UK report implies the fire started due to an oil leak onto the hot exhaust.

The car was waiting on the side of the road for 3 weeks before being collected for inspection by BMW where it got vandalized while waiting to be collected. Plastic can be seen in the threads of the place where the plastic oil cap once was. The alloys are melted, yet it is claimed the polymer is heat resistant. The car exploded few times while burning. The grass on the opposite side of the road was burnt.
 
So BMW UK report claims that the fire occurred due to a missing plastic oil cap.

We'll assume for a second that this is true.

The question I ask then is:
Does BMW i3 Rex have an oil pressure sensor? I cannot seem to find one in any technicical literature.

And if it does, does it have a red "oil" sign in the dashboard to indicate such locc of pressure/oil?

Perhaps those of you who got an I3 rEx may be able to help. I don't remember ever seeing one lightning up on the dash when turning on the car, as part of the dash lights check.

Why does BMW i3 not have an oil pressure sensor?

What is the Type approval underpinning the obligation to fit a vehicle with warning devices such as low or no oil pressure?

How come that no warning lights whatsoever showed up on dash?
The oil filler cap to my understanding is only there to prevent minor spills and contamination from outside dirt. It's not pressurized.

The report suggests that some (likely spoonfuls) oil eventually spilled out of the (uncovered) filler opening and caught fire on hot engine components. That's not something an oil pressure sensor could detect. I'm sure oil pressure inside the rex engine was still normal during the whole episode.
 
Definitely a UK term, though of course it could be a translation of a different European term. But odd for a UK resident to quote an EU safety organisation which doesn't (as far as I can tell) even cover the UK any more. Very odd...
I live in Ireland. Which is part of European Union.
 
"Vehicle was imported from the UK". That may explain why there was no mechanism to link your car to any recall? As far as can tell, recalls are country-specific and so there would be no provision for it to follow you from country to country.

But, having said that, I don't think the main recall for the car had anything to do with the oil filler cap - IIRC it related to the proximity of the fuel tank vent pipe to the HV cabling (and only applied to some cars)?

Unfortunately for you the conclusion from BMW doesn't really help you. The oil filler cap might have dropped off while the vehicle was in motion, or someone may have forgotten to refit it after the last service?

Fortunately it seems clear that the fire was not electrical, so you should be fully covered (though you have to question the value of comprehensive insurance for an EV that excludes electrical faults!).

[And just to re-iterate what Mendomensch has already said: on that engine, the oil filler cap would not be part of the pressurised oil system. You would get no loss of oil pressure if the oil filler cap were missing, unless a significant proportion of the engine's oil had already escaped through it.]
 
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"Vehicle was imported from the UK". That may explain why there was no mechanism to link your car to any recall? As far as can tell, recalls are country-specific and so there would be no provision for it to follow you from country to country.

But, having said that, I don't think the main recall for the car had anything to do with the oil filler cap - IIRC it related to the proximity of the fuel tank vent pipe to the HV cabling?

Unfortunately for you the conclusion from BMW doesn't really help you. The oil filler cap might have dropped off while the vehicle was in motion, or someone may have forgotten to refit it after the last service?

Fortunately it seems clear that the fire was not electrical, so you should be fully covered (though you have to question the value of comprehensive insurance for an EV that excludes electrical faults!).
I do not find the report believable.

The rex was in a fire for 9 minutes. Regardless of the cause of the fire, there was thermal runaway of the battery at some stage. there were repeated explosions during those 9 minutes, which I believe to be associated with each of the modules exploding. The grass of the other side of the road was burnt and the wheels melted. The car sat for 3 weeks on the side of the road. To say that a plastic cover could not be found after such fire, is... funny. Neither can be the the air intake manifold, the two child seats, my fire alarm testing kit, nor most of other belongings. However, I will say that the range extender was turned on from the very start of the journey, some 20-30 minutes before the fire started. If it was indeed the case that the oil cap was missing, the car would have gone on fire minutes after the oil change, not months after that.
The most fire debris was located at the back of the electric motor. And as can be seen in the photos, the insulation on the High Voltage cables is completely melted. Is BMW saying that the oil cap couldn't melt but the High Voltage cables insulation could?

Nevertheless, there were no warnings, faults, or anything else showing on dash.

I cannot seem to find an oil pressure sensor anywhere on the rex. I also cannot remember seeing a red oil warning light on dash. Which raises the question whether in the event of an oil leak, will others be as lucky as myself to manage to get out alive or should the I3 rex be recalled due to a design fault?
 
If it was indeed the case that the oil cap was missing, the car would have gone on fire minutes after the oil change, not months after that.
I don't think that's necessarily the case. It's hard to get oil out of even an open oil filler neck. It's also hard to get an actual oil fire started, even once exhaust components get hot.

However, I wonder if potentially oil could have leaked out somewhere else in the engine? Again, there would be no effect on oil pressure. Are there any signs of oil drips on the ground where it was parked? Super hard to figure things out after such a destructive fire.

Seems to me that having the engine hidden away under a trunk panel makes it a lot harder to monitor engine condition than when it's visible under a hood. I know on my ICE cars I always take a look under the hood and check oil level and look for obvious drips and leaks every couple of gas fill ups.
 
Was the car imported to Ireland from the UK? If so, I don't think you can make any assumptions about the "standard" recalls process.

If you look at a diagram of the W20 engine you'll see that the filler is right at the top of the engine. It's not surprising that any leakage from there could take quite a while to work its way down to the exhaust manifold, which is the only place where it could get hot enough to ignite, and for the manifold to get hot enough to cause ignition.

I've had a similar issue (with a completely different engine) and it can take a long time before the crankcase pressurises enough to "spit" oil out of an open filler neck. In my case it was a front-engined car, so I saw it long before enough had escaped to cause a fire - just a lot of smoke!

Is your insurance willing to cover the loss? If so, your best course of action may simply be to take the insurance money and move on. It's relatively easy to speculate about things that might have been done wrong - but proving it will be a different matter, and you could expend a lot of potentially wasted effort trying to do so...
 
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I don't think that's necessarily the case. It's hard to get oil out of even an open oil filler neck. It's also hard to get an actual oil fire started, even once exhaust components get hot.

However, I wonder if potentially oil could have leaked out somewhere else in the engine? Again, there would be no effect on oil pressure. Are there any signs of oil drips on the ground where it was parked? Super hard to figure things out after such a destructive fire.

Seems to me that having the engine hidden away under a trunk panel makes it a lot harder to monitor engine condition than when it's visible under a hood. I know on my ICE cars I always take a look under the hood and check oil level and look for obvious drips and leaks every couple of gas fill ups.
No leaks anywhere. I always parked the car in the same spot. Moreso, I washed the car the day before, so I would have noticed.

The engine collapsed entirely during the fire. So it went from an upright position, rotating around it's axis some 90+ degrees. Hence the oil leakage on the rocker cover. The car was then lifted up by forklift and moved off the road. The engine was still on its side.

I absolutely agree that it is near impossible to determine the exact cause of the fire.
 
Probably irrelevant, but under what circumstances does insurance not cover for an electrically-caused fire? That sounds like an absurd fine-print exclusion.
 
I cannot seem to find an oil pressure sensor anywhere on the rex. I also cannot remember seeing a red oil warning light on dash.
The REX engine does have an oil pressure sensor but, as Mendomensch has already said, the oil pressure light would not come on if the oil filler cap were not present.

You can't read any significance into the possible lack of a dedicated warning light on the dash - many modern cars use text messages on the dash in place of dedicated warning lights. It's likely that the car would disable the REX engine operation if low oil pressure were detected, but it's also likely that it would continue to operate in battery-only mode - assuming enough power left in the battery.
 
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