Cyclone seperators. If you’re not familiar with that phrase and you drive something with an M54 in it, you’d better read up as you’ll be replacing it at some point in the not-so-distant future.

The rear subframe on the E46 is weak. Or, more accurately, the portion of the unibody where the subframe mounts to is weak. Woo hoo for unreinforced sheet metal! I’m a bit jaded about that issue particularly as I had to take a $20k loss on my E46 M3 because of it. Thank you, BMW. We’ve seen (and repaired using the Turner Motorsport kit) a few cracked rear subframe mounts.

Just be glad it’s not an E36… They had weak front and rear subframe/strut towers. There’s nothing quite like having to hack and weld on your otherwise OEM car because BMW just didn’t put much thought into mounting an integral portion of the car’s chassis to tissue paper.

Then we get into sunroof cassettes. I’ve seen them fail as early as 35k miles (but out of warranty due to age). Most of them manage to somehow make it to 100k. The dual-sunroof cassette in my E34 touring is trash, too, but with 262k+ miles, I’ll give it a break.

BTW, I haven’t heard about particular problem with window regulator in E46 (I even had 330ci E46 and hadn’t noticed it) and suppose when it appeared, it came from bigger malfunction of electric net with which few of my friends told me. The biggest problem with E46 about which I know is problem with fasten of rear axle to platform in early production models. But once again, it’s something that revealed after some milage and not in each E46 from early production phase.

Ask anyone with an E46 or newer BMW about window regulators. Ask the E36 (and other M50/52 platforms) about water pumps. Ask the N62 guys about the vacuum pump and its tendency to flood the brake booster with oil…

The bottom line is that these systems are designed by humans, which inherently will make mistakes. I’d even go as far as to say that BMW (and every other car manufacturer on this earth) doesn’t spend nearly enough time in R&D testing a vehicle before launch. It’s just simply not realistic given the market demands of churning out a new model NOW!

There will be issues, and I’m sure BMW will either continue to resolve the issues as they come to light (many will likely be after the vehicle’s launch) or they’ll just scrap the idea before even implementing it on a retail vehicle.

The problem with all of these is that they’re so unfocused. What carmakers need to do is develop a thermally insulating coating for the cylinders, pistons, heads and exhaust manifolds so the heat is focused tightly for a very high temp differential (and never gets into the engine block or dissipates to other components). There are some composites that do this quite well, used on theof the leading edges on some aerospace applications.

Having concentrated most of the heat energy on the exhaust, you add an air-to-air or air-to-water thermocouple there, perhaps combined with a catalytic converter (assuming it’s not cooled too much). THe temperature differential will be enourmous, and you will gain FAR more power from a much smaller, simpler unit. Additionally, you will save weight on water/plumbing/radator as well as exhaust system since that has been condensed.

All these scattered parts gathering a few percent of the wasted thermal energy is not really shooting high enough.

However, the electric shock idea is a very good one (I think Bose owns the patents on this though).

The same thermodynamics that make the BMW EngineSnuggie work to improve efficiency at start-up apply when the engine builds up excess heat either due to a malfunctioning (neglected) cooling system or simply stuck in stop-and-go traffic in a warm environment.

The concept is sound. I can absolutely see where BMW is going with this… I’m just not sure that it will turn out to be a fantastic idea in the long run.