I changed my own oil but my dash says -100 miles until oil service. I have a 2000 328i sedan. I know you can buy a service reset tool but since I changed the oil and filter myself I am sure the dealer isnt going to be too keen on reseting my computer for me. Anyways, is there anyway to reset this to say 15k miles until next service without buying the reset tool and if not where can I buy the reset tool. All help is appreciated.

There's a reset procedure that involves a combination of turning the ignition on and off and pressing the left button on the cluster, but I don't recall the exact sequence. Maybe try the E46 forum.

You can try:

- Iginition OFF (POS 0)

- Press and Hold the trip odometer button while turning key to position 1
(ACCESSORY)

- Keep the button depressed (about 5 secs.) until you see "Oil Service" or
"Inspection" with "Reset" or "Re" in the display

- *Note: On vehicles with "High" cluster, you will also see the amount of
fuel (in litres) remaining until next service

- Press the button again and hold for approx. 5 secs. until "Reset" or "Re"
flashes

- While the display is flashing, briefly press the button again to reset the
Service Interval. After the display has shown the new interval you should
see "END SIA" for about 2 secs.

Note that if the "Reset" or "Re" does not flash, then you have not met the
minimum consumption level and cannot reset.

It works for me on an '01 E39, but only if the "Oil Service" is on. If neither the yellow or red bars aren't on you haven't met the minimum fuel consumption and it won't work.