This procedure for the V8 BMW 540i and 530i is pretty simple.
You might want to change the valve cover gasket while you
are at it of if your spark plugs have a lot of oil on them.
1. To access the spark plugs for removal, you
first need to remove some plastic housing on the engine. To
begin, you must remove the (4) engine cover nut caps and the
(2) ignition coil/spark plug cover nut caps to expose the nuts
2. After removing the nuts securing the engine
and ignition coil / spark plug covers, you next need to slide
the grommet on the throttle cable entering the front of the
engine cover out of the engine cover so the cable can drop downwards
out of the hole in the cover when the cover is lifted.
3. The cover can then be lifted upwards (see picture
above) to allow for removal of the ignition coil/spark plug
4. After you have removed the ignition coil /
spark plug cover, you will now have access to the ignition coils
and ultimately the spark plugs. As you can see below, (2) nuts
secure the ignition coil in place. To remove the ignition coil,
first, loosen and remove these nuts. Note that the ignition
coil springs up slightly as you loosen both nuts - there is
a spring inside of the ignition coil stem that makes contact
with the spark plug. In the secured position, this spring is
slightly compressed and pushing against the spark plug and thus
the coil rises up slightly as you loosen the ignition coil nuts.
After you have removed the nuts, you need to next disconnect
the ignition coil harness from the ignition coil. This is done
by sliding the harness release/securing latch outwards to unlock
the harness, it can be unplugged from the ignition coil and
the coil can then be removed.
As you can see above, the spark plug is now accessible
Reinstallation is the opposite of removal.
note -the OEM spark plug for this engine does not have an