He encontrado este texto en ingles con los principales problemas para la seccion a tener en cuenta pero no consigo traducirlo bien si alguien sabe y quiere que por favor lo traduzca(muchas gracias):
Known Problems Rust, be very afraid of rust. Look at inner wings, sunroof channels, rear suspension turrets. Many E23s have TRX alloy wheels although early cars had 14" alloys. TRX's use a special size of tyre which is difficult to get and very expensive. Most owners fit 15 or 16" wheels to improve handling. Electric seats can fail, especially headrests. Pre 1980 engines have larger waterways in the cooling system than later models. This can sometimes cause the head to crack. If the car overheats in traffic check the viscous fan coupling and the two speed electric fan (fitted to A/C equipped cars). Check water hoses haven't perished, especially the smaller ones. Check alternator bushes and mountings around 100,000 miles. Not hard to replace. M30 engines can suffer from oil starvation on the camshaft resulting in damage. This is preventable with a new design of hollow bolt for the oil feed bar. ZF 4 HP 22 automatic transmissions can fail due to a blown A clutch pack if revved strongly whilst in neutral or park. Rubber engine mountings can perish, check engine isn't tilted forward and air flow meter is aligned properly. Post 1982 models have a more reliable nylon "guibo" propshaft coupling insert. Check differential mountings have not loosened and lowered the diff. Worn rear subframe bushes can make car waver on the road. Carefully check fuel lines and tank for corrosion. The tanks rust at the base of the filler pipe, only visible with a totally full tank of fuel. Seized rear brakes are due to collapsed rear brake hoses. Flashing ABS warning light often means that wheel sensors are rusting badly. Some owners disable the warning light so check it glows orange with the ignition on but the engine off. Heating can stick fully on or off due to faulty heater control valve, not expensive to fix. Bad solder joints on the control unit or the two sensors can also cause problems. If the fan works full on but not on variable speed then the transistor is dead. Test with the A/C on and off as there are two motors and controllers. Check all the electrical goodies work, bits for these ain't cheap but they are generally reliable. Best buying tip? Get a specialist to check it over and never assume rust is minor.
Un saludo y gracias otra vez.