Back in the days before black boxes, a BMW tuning actually meant something. You would change filters and PCV valve, clean and gap or replace spark plugs, replace points and condenser, adjust and clean or rebuild carburetor, adjust timing, replace distributor cap and rotor. A tune up was for engine tuning. Modern engines have almost none of the above parts. Today, replace air and fuel filters, PCV valve and spark plugs. That's it. If you have a distributor, replace the cap and rotor, but many cars have coil packs now. Serpentine belts last forever and I haven't seen a radiator hose fail in years. Ignition timing is no longer adjustable and everything is fuel injected. Are there other things (plenty mentioned already) that you can check as part of a regular checkup? Yes. But a tune up these days means almost nothing. Be particularly wary of shops that offer a tune up special or some such thing. You may be paying through the nose just to get a set of spark plugs. That`s it: you learned how to tune a car, a BMW, really amazing car.
