I bought the car with a bad alternator. I have gone through two more since then, but I believe that to be the fault of the alternator remanufacturing company, rather than the car.
Speedometer was inop when I bought the car. The fault was in a broken speedometer cable, which was fairly easy to replace, if somewhat time-consuming.
The driver's side power window was nonfunctional when I bought the car. I determined the problem to be in the motor, and was able to replace the faulty motor with an Ebay part for only $45 or so. Replacement was not at all difficult with hands small enough to fit inside the door panel.
The original leather driver's seat has worn badly in the car's seventeen-year life. I plan to recover the seat. Also, the leather cover on the steering wheel has worn very badly, and the shifter boot was torn when I bought the car. Replacing the shifter boot was very easy and quite inexpensive.
The radio aerial was eaten by a low tree in my yard. Replacement was somewhat difficult, but the factory antenna, with cable, was very inexpensive.
The factory stereo would not output to the left channel while the tape player was in use. I replaced the stereo unit with a CD/MP3 player and am very happy with it now. Replacement was the fastest and easiest of all of the cars I have installed stereos in.
The original dash speakers had begun to crackle by the time I took ownership of the car.
The synchronizers have begun to wear, especially in second, third and fifth gears. The gearbox has never been rebuilt. I will do this myself within six months, at the same time that I replace the clutch. The gearbox has an audible whine in the very top of third gear.
The original muffler had rusted through and developed a hole the size of a golf ball. My car sounded like a Honda until I had the muffler replaced last month, at a very reasonable cost for such a large, oddly shaped muffler as the MR2's.
The props for both the engine cover and the front boot have broken their clips, and now rattle incessantly when driving at any speed. They are not so loud as to be intolerable, but the rattles are always present and irritating at times.
Both rear strut cartridges have blown their seals, causing serious wheel-hop upon breaking a tire loose. Taking a corner too fast, while accelerating, can cause the car to shudder violently until the driver lets off the accelerator and regains traction.
The car's paint has stood the years well, but the black plastic trim on the sail panels has faded badly. Also, each of their retainers has either cracked or will very soon. These trim parts are very rare, and will not be cheap to replace.
The original weatherstripping still seals well. My car has no leaks, around the windows, the doors or the sunroof.
Air conditioning does not cool as well as it should. I will be converting to R-134a within one year, and will solve any problems at that time.
The clutch has begun to slip more than I would like, under hard acceleration in gears. This is a normal wear issue, but needs to be replaced soon.
The cabin trunk-release cable has been broken since before I bought the car. Replacement will be difficult as it is routed through the firewall into the engine bay, and then out into the trunk. I will wait until I replace the clutch and engine before I attempt to install a new trunk-release cable.