i,ve read the f.a.q threads and have gained alot from them. my 83 320i was my wifes car when she was 15. her daddy bought it for her and she drove it to school and what not. she later got an aircooled bug and the beamer was put away in the familys warehouse..it was loaned out to multipal family friends, and pretty much just treated as a spare car. well me and the old lady flipped the kia we were driving, rendering it pretty much useless, so the bmw got taken out of mothballs...i'v drove it about a year now...i worked on chevys most of my life and the beamer was fairly exotic to me.. i got the haynes manual and have done multipal repairs....first to go was the slave cylinder for the clutch..the piston popped out and fell down into the bell housing...i am so glad this happened as i was going to start it and not shifting gears, as the flywheel to housing clearence is tight.....i took the tranny out with a crappy autozone floor jack, my skateboard, and a 2x4...the propeller shaft was a fun discovery...it all went back in and works good.....next was the starter...it wouldnt start the same way my chevy wouldn't..i looked at the starter and that fun feul injection setup on top of it and decided to replace the solenoid and see if it helped.....it started and was fine for a while ...then it left me stranded at work..my father in law, who is more of a "throw money at the problem" kinda guy wanted to put it in a shop..he had it towed to a shop he used before ....they came back with the diagnosis of bad ignition control unit..they replaced it with a "hugo" brand unit which says made in germany, but it isnt bosch....they charged $200 to replace this which i see is two screws and a wire clip, but the problem is it wont run right now...the moment i got it back i knew somthing was wrong. it bogs in the low rpms and doesn't want to start after it has warmed up ....also the balljoint was trashed causing a big shimmy between 35 and 40...which it didn't do before...i have a strong feeling they took it and beat the crap out of it then returned it with a bill...never again will i let annnnnnny shop touch my car..i replaced the balljoint ,control arm & bushings....ebay cheapo...shimmy gone.........well my question at this point is what does the ignition control unit do?...is it tied to the distributer or the starter....the haynes is no help...could it be bogging the low rpms..the whole feul distribution unit is new to me and the whole system seems over complicated...i have the wire gremlins going on too, hazard switch has a shim, battery light is on, i don't drive at night because my passenger side marker lights overheat the circut and pop..my positive cable gets real hot....i read about the wiring problems....this car will never be sold as it was my wifes first car so i'd like to sort it all out.. i pretty much just don't know where to start..thanx for any help i get, i'm off too inspect wires for now.....any more on this chevy alternator swap? the asstro van one..seems more up my alley...i want subs and it would be scary at this point...smoke and fire and all ...........thanx ...peace

Hey welcome to the forums. The ignition control unit (ICU) can either work or not. It can't cause any sort of running problem. If it works the car runs, if it doesn't it wont run. They almost never go bad their conspicous location means they are often wrongfully accused.
Probably you need to clean or replace the battery cables and clean every electrical connection you can find.

what exactly does it do though?

also can the starter motor itself be replaced without pulling the intake?

Have you checked your timing? My son and I just re-adjusted our timing; his was too advanced, and mine was the opposite. My timing was causing a bogging at low rpms. When it was advanced a bit (nearly 1/2 inch!), the low end torque came back.
My son's idle was rough, but now it purrs.
Hopefully, this is your problem too! Best wishes...
Tim

The ICU is elegantly explained here: http://forums.bimmerforums.com/forum/showthread.php?t=862377

And yes, you can and I do reccomend changing the starter with the manifold in place. If you loosen the fuel distributor where you can move it around a bit (maybe take the brittle lines loose so you don't break them) you can get the starter past it. Its a good chance to replace the intake boot too (the black rubber thing under the manifold) since an old hardened one is really hard to reinstall.

where can i learn more about the real nitty gritty workings of the feul system. ideally i would park this car and tear into it but it is my only transportation and i have a family to feed.. i need to learn alot more before i get into tearing it apart.. i basiclly need to familiarize myself more..

yeah , my intake boot is duct taped up too..i gotta lot of work before i even think of m20s, turbos, or rims..thanx

Hey roadkill, I'm just up the road from you in Olive Branch, MS. I'm new to BMW's also....so I can't help much. My wifes dad bought this one new in 82 and gave it to us last year. I'm going to make it an IS clone, just because I like the IS parts. It runs great, but looks bad. David