I don't see this *important* info posted often so thought I would start a thread to see what everyone is doing to keep thier F/I cars running at top performance. Hopefully everyone is aware that F/I puts a lot more stress on your car's parts that are designed to wear and be replaced. Please post what's on your list of items to check and how often. Here's mine..
Engine Oil/Filter: I believe BMW recommends servicing the oil/filter every 15k miles, even for a n/a car with no mods that seems a little long to me. I may be on the extreme side of caution but my cars gets new oil/filter approx every 2 -3k miles.
Air Filter: Easily overlooked, if you're sucking in a lot more air your filter is going to collect dust and debris a lot faster. Last time I cleaned mine I was a bit overdue. I now clean and oil my filter with each engine oil change.
Transmission Fluid: BMW claims the tranny fluid is good for the life of the car, although they even recommend service @ 100k miles. My car has 50k miles on the clock (most of that was n/a) - I'm planning to change the tranny fluid soon.
Differential: Don't recall what BMW advises - I just changed mine recently. (Wear some kind of gas mask, the diff fluid smells like Sh!t.)
Flex Disk: If you're unfamiliar this is the ultra strong circle of reinforced rubber that connects your transmission to your drive shaft, I replaced mine about 5k miles ago as it was cracked and splitting everywhere. Replace as needed.
Spark Plugs/Coils: I generally replace these as needed. I keep saying I'm going to pony up for the Okada Coils, so far the $1k+ price has deterred me. If you own a HPF car they have recently upgraded to a new high performance plug that is quite expensive, but runs cooler, is pre-gapped, operates more efficiently, lasts longer and puts less stress on your coils.
Methanol Injection: If your car has this remember to add two teaspoons of "Alcohol Fuel Lubricant" per 1.25 gallons of methanol. See this thread for more info: http://forum.e46fanatics.com/showthr...fuel+lubricant
Coolant: I live in Texas and it gets HOT during the summer months. In the summer I add a mix of distilled water and 2 bottles of Watter Wetter. In the winter months I go back to the oem BMW coolant.
All I can think of for now. Look forward to hearing other's rec's.