Running strong to power stuttering to dead.

[Farrva]

Hi All,
I just picked up my first E30 - 1986, 325. I actually drove it from Detroit to Burlington VT (780 miles) with NO issues whatsoever. In fact it ran so strong, I'm very surprised it just died on me 30 minutes ago. Here is the development:

Ran VERY strong over 2 days of constant driving Nov 19th and 20th. Got it home, gave it a detailed wash over and under. Parked it that Sunday and didn't drive it until last Tuesday just around the block. This is when I noticed after a good 7 minute warm up in 35 degree weather it started to lightly stutter with the power under 2k. The power would suddenly come on then run strong again over 2.5k. This was especially prevalent under load, even on the slightest incline. This was accompanied by a buzz sounding like Morris Code, which I believe is was fuel pump.

I've driven the car 3 other times since then and each time the symptoms progressively got worse. The buzzing was sporadic, I thought this was due to the cold. The last 2 times it started to smell like something was rubbing pretty hard. There are no other sounds. Once warmed up, the idle was around 600 and was a little rough. I drove it around the block to try and trouble shoot, not to joy-ride, to be clear.

Today there was no humming from the fuel pump, but the power loss was worse than ever, and as soon as I turn in to park it sounds like its mis-firing and the RPM's dropped to nothing, the radio shorted out, and lights dimmed. I cut the power immediately halfway into the spot. I tried to turn it over and nothing. All lights came on just fine, but nothing else happened.

WHAT IS THIS?? It was running so well!

I was planning on working on the car myself to learn in the Spring as I do not have any time to do so now. In anticipation of something worse coming I had already scheduled an appointment with BMW this coming Monday (I have not found any reputable classic BMW specialists in the area), then directly from there I am putting it into heated storage for the winter.

What could this issue be? I would like to fix it so I can actually drive it to the mechanic...

Thank you!

Pictures and details to the beauty here:

http://www.ebay.com/itm/1986-BMW-3-Seri ... 7675.l2557
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[Farrva]

UPDATE: It's now turning over and tuning again. However same symptoms remain.

Does anybody have insight?

I see many mixed comments on similar threads, however I have not seen one where the car doesn't even start.

Any advice is greatly appreciated.

[Brianmoooore]

The first part of your post sounds like a failing crank position sensor or possibly DME relay, but then you go on to describe a smell and dimming lights, which sounds like something seizing around the fan belt area, and slipping the belt.
Easiest and cheapest (free) thing to check is the DME relay. This is a five pin relay, usually white, and lives under the plastic cover on the inner wing, near the air filter.
Pull it out, identify the pins of its base, which are marked on the relay, then use two short pieces of wire to link together the 30 pin and both 87 pins. Start and drive the car like this, but don't forget to pull out the links when you park, or you will flatten the battery.
Other things to do is a thorough check of the condition of the convoluted large air hose between the air meter/filter and the throttle body, and, if your battery is in the boot, open up the phantom battery terminal connector box on the bulkhead behind the front battery tray, and fit a temporary wire link between the two terminals there.