I saw on the news today where BMWs have been catching fire while parked and inactive for several hours or even days. They say it is a mystery and BMW denies any pattern. How could something like this be a mystery? They showed at least 10 that were burned up and stated there were many more. I would think this would be easy to find and that BMW denying a pattern could really be hurting their own stock once this becomes widely known. I would rather see a company say they were right on it even if they hadn’t figured it out yet.
With only a relative handful of cars affected so far out of millions sold, and the evidence burned up in the fire, how could it NOT still be a mystery? I don’t know why you expect it to be obvious what the cause(s) would be. Seems to me the car would have to have the fire extinguished very shortly after it started in order to have a chance of locating the origin point.
Decades ago Triumph TR7’s had a similar situation, with some cars experiencing spontaneous fire under the hood. It was finally sorted out that the horn relay, installed terminals-up on the side of the engine compartment, could take in some water which caused a short circuit. Although all the cars had the same design, fires occurred in only a small percentage of them. It took some time, and probably some luck (e.g. ending the fire before the car burnt to ashes) to track down the cause. (There was a recall, and the fix was to remount the relay so the terminals pointed down, making water ingress impossible.) ETA: The fires would often start while the car was parked, as it took some time for this type of short to generate enough heat. Hence there was no discernible cause/effect relationship to anything the car had done.
This is the kind of thing that’s easy to understand after the facts are known, but often very difficult – sometimes extremely difficult – to figure out when it first arises. Typically there’s no history of the specific type of problem on any cars (anywhere/anytime) to take a clue from. It’s really not that easy.
This article quotes the statement from BMW:
Seems like a reasonable statement to me. By “no pattern” they mean the vehicles that caught fire don’t have specific things in common that could be causing the fires. I’m not sure what more you could ask for.
Gary I don’t think it would be easy but as yourself I spent 45 years in the industry. A big part of my job involved looking for patterns on failures. The horn relay was a good example of this. That would have been hard to find but upon close examination of all the parts in a given area knowing how it was wired would have made it much easier. We had a truck that burned up and was towed to my shop. The driver survived but had horrible burns over a large part of his body. I was surprised when the factory reps claimed they could find no cause that was truck related when it was very obvious to me that the diesel injection into the exhaust for a cleaner afterburn was the specific cause. It sprang a leak and started spraying on the exhaust manifolds. I don’t trust companies.
This makes more sense, this wasn’t the answer from BMW I heard. It is the type of answer I would have expected. It sounds a lot more credable.
They are The Ultimate Driving Machine. You’re not supposed to* park* them!
Burns More Warmly
But what if you park them on a driveway? Or drive them on a parkway?
Possibly the driver or passenger left an electronic device such as a cellphone or an e-cig with a defective battery in it which self ignited (or perhaps a haha skateboard).
Here’s an article from Jalopnik with some perspective on ABS’s reporting…
Burn My Wheels.
Bring More Water?
I don’t know. Mine haven’t caught fire in the last 40-20 years. I figure I’m safe. Jennshark might be in trouble, however. She likes that new shit.
I don’t think I could set fire to an e30 with a flare and a gas can.
Reminds me of the (old) joke about a a CPU engineer and automotive engineer arguing:
“Why, if autos were like computers they could go 300-mph and get 500 miles to the gallon.”
“Yup, and at random intervals for no discernible reason, they’d explode killing everyone on board.”
This makes me feel just a little bit worse about shutting the cat in the garage at night.
Running footsteps, door opens, door closes, footsteps back to couch.
Phew! No blackened Bavarian hulks smoking in the driveway! (yet).
Because the entire Dope didn’t sleep well wondering if I blew up overnight . . . all is well 
The guys at Jalopnik and a few other gearhead sites claim that the episodes are overblown (hee hee) and not statistically out of line with other cars burning. I’m actually more concerned about reports of X3s being stolen using their wifi connections.
I actually did start two cars on fire last summer. My senior BMW wouldn’t start, so after a very frustrating afternoon of trying to jump it with my neighbor’s portable battery, I hooked up my Jeep to jump BMW Sr. I was tired and pissed off and accidentally cross-connected the jumper cables. Both cars’ batteries started on fire, I still have fire extinguisher chem stains in my trunk. (Both cars survived). I learned two important things: that BMWs should be jumped with the posts in the engine block, not the actual battery, and I should should not do things when I’m tired and pissed off.