Hazard light switch replaced twice since I've had the car. These things are notorious for failing.
Cruise Control doesn't work (and apparently never worked well, as per my Uncle).
Bad front-end shimmy that is very difficult to repair.
Interior upholstery is worn out. Covered rear bench seat with towels and pulled two black-vinyl Recaro seats from a junked 320i and replaced front seats. What an improvement. The musty smell took about 6 months to dissipate.
Center console assembly replaced- found used set on eBay.
Glove box straps break easily.
Blue smoke at start-up, some oil consumption. I've heard they did this when they were brand new.
I got this beautiful black car as a senior in high school (18 year old kid driving a car about the same age). I got many compliments on it then and I still do today.
What a fun car to drive, despite its "quirks." Aside from people asking me how to open the doors from the inside (you just have to own one to know what I mean) and why it creates blue oil smoke when started, it's a relatively cheap and basic European car.
Handling is excellent and the ride is very German, although there is a little body roll when tossed around during more spirited driving. The front-end shimmy is part of owning the e21 and only a few people know how to fix it. Don't trust anyone, but a well-respected BMW mechanic to do your alignments.
Acceleration is so-so. The 4-cylinder engine feels stressed to move the somewhat heavy car from a standstill, but given the gas crisis at the time of its manufacture, I understand. I've thought about replacing the 1.8 with a 2.3 straight-6 when I get money.
Owning this car and keeping it in top shape requires quite a lot of time, dedication, and some extra money. And don't forget hours of elbow grease and lots of Zymol wax to make it shine!