My wife's car, the four door 1997 318is, has developed several faults over the last few months. The most annoying is that the exhaust manifold seems to have developed a crack, which I believe is a common fault with the M44 manifolds. It's been like this for some time now but I have finally got around to buying a second hand manifold from a local wrecker (A$100) but am yet to install it.
Another fault is that the ventilation system is stuck on heat. This is also a common problem and the usual cause is the heater coolant valve in the engine bay up against the firewall. This will be the third E36 I have owned with this problem. I haven't fixed this problem yet either but will find a second hand part and fit it soon. Unfortunately this means bleeding the cooling system again, which is not a fun job.
Lastly the air bag light has come on. I have yet to connect the fault code reader to find out the cause.