Currently I'm in the process of tuning up the ignition system by replacing the distributor caps and rotors, plugs and plugwires.

The reason for this is that I discovered the drivers side coil-distributor cable had a nasty cut in it due to the cable strip BMW has used to hold it in place with a hose. This caused sparking to nearby ground and almost made the plastic in that area melt away.

This all caused the car to be hard to start and run very rough, and having problems rev'ing. I made a temporarily fix and made the car run very good by fixing the coil-distributor cable with some duct tape. Don't laugh, it worked, but I've also ordered and received a new cable.

While at it I decided to check up on the distributor caps. The drivers side were actually rather good. Though the manufacturing date of Feb 1989 made me decide to buy all new ones. And I don't regret that after I removed the passenger side distributor cap. The center pin was all gone and sparking had obviously happened since it was very sooth fiiled around the center. Amazing design since it didn't even run very rough! 

By a mistake I decided to change the camshaft position sensor on the drivers side. I discovered there's one on each cylinder bank that is connected to the front of the engine by snap-connections. In my "wisdom" I measured the top two ones, but these are actually cross-connected so that I measured one camshaft and one crankshaft position sensors.

Crankshaft position sensors remain connected

Deeming one bad since I got very different values (around 0 and 480 ohms). Later I've found that they are all ok. Both crankshaft sensors measure 480 ohms, and both camshaft measure 0 ohms. By the help of bimmerboard.com I've learned that the car won't run if the camshaft ones are faulty since they control when the fuel is to be injected.

I pulled all the sparkplug wires when I decided to replace the one camshaft ones since these sensors are integrated into the 6th spark plug wire on both sides. They cannot be removed unless you cut of either the distributor cap plug or the spark plug to slide the ring sensors off.

I've ordered up 10 meters of spark plug wire to manufacture new ones using the old booths as they are most likely ok. It's also much cheaper! The whole sparkplug wire set is close to $900. You can substitute these with others I've heard, but having some time to finish this project I decided to try and make new ones while I'm at it. Otherwise I'm sure Murphy would come visit and haunt me later. And it's a real pain to remove these wires and plugs so why not do it when I'm already having out lots of stuff in the enginebay... I'll also have the knowledge that everything is new and working for some time to come.

My car is also fitted with EURO2 GAT/KAT conversion kit to help aid speed up the heating up process from cold and reducing emissions (thanks shogun for the valuable tips and info).

I plan to move this electronics into the cabin where it's not subject to wind and weather like in the engine bay. It's not too complicated and there's plenty of wiring to move it about.

More updates will follow.