Original exhaust replaced around 180,000 miles.
Transmission rebuilt around 215,000 miles.
Lower control arms now need replacing.
Air conditioning went out around 220,000 - I never investigated the cause (might be minor).
Other small misc (to-be-expected) items replaced as well as preventive maintenance.
Gasket at the oil pan has small oil leak.
Electronic module (ignition related) - I got a used replacement for less than $50.
This has been a GREAT car! I still prefer driving it to my wife's 1999 Mitsubishi Eclipse. It handles better and is just about as fast (maybe more on the top end).
The interior is well designed except for the lack of tilt steering wheel and no air bag (was optional in 1987).
Very low maintenance required (until around 200,000) and the engine still runs strong.
Original black paint looks great with 2 small spots (smaller than a dime) of corrosion around the rear license plate lights.
Car stranded me one time in my 11 years of ownership (due to an electronic module).
The 325i has a 2.5 liter straight 6.
If he has a 325 (not 325i), it's a 2.7 liter I6 just like in the "e" and "es". The "i" and "is" were 2.5, as you said, and all were inline sixes.
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