How do you replace spar plugs on BMW 323I?
I can answer this for my 1998 323i convertible but will likely apply to others as well. You need to remove the engine cover that says BMW on it. This is easily done by popping off the two plastic plugs on top of the cover and removing the two screws. (you will also need to remove the oil cap.) Be careful not to lose the gasket that surrounds the oil cap opening. Beneath the cover there are 6 square spark plug cables in line, each attached with two bolts. You need to remove the two bolts... disconnect the square cables and pull them out. The plugs are about 6 inches into this hole and you will need an extension on your plug socket to remove them. The last plug is a little tricky because of low clearance. You may need to stick the socket and extension into the opening first, and then clip the wrench onto the extension. FYI, all the nuts/screws you need to remove are 10mm and some can only be accessed with a socket. The plugs are standard 5/8 plug socket. The OEM plugs are like the Bosch Platinum 4 and are pre-gapped. Dont use junk plugs. Spend a few extra bucks and get the OEM or Bosch.