Doing a tune-up on my 91 318is

[achtunge30]

M42 engine, what do I need besides...

ignition wires
plugs
fuel filter
air filter

Is ignition coil also part of the service? What else am I forgetting?

[asubimmer]

do you have any idea how much spark plug wires are for the m42? 200+

oil
redline tranny and diff fluid

[KenC]

The M42 actually has 4 coils, and you shouldn't have to replace them during a routine tune-up.

I'd do:
oil change with filter
air filter
fuel filter
spark plugs
cap and rotor
coolant if it hasn't been changed in a while, same with the tranny and diff fliud

[asubimmer]

IIRC the m42 is doesn't have a distributor, so that would mean no cap & rotor

[Febi Guibo]

use stock/OEM plugs and wires... while yer in there... get a new timing chain tensioner

[02stu]

Check the timing chain tensioner. Alot of m42s die because the tensioner fails and ether breaks the chain or the timing chain gear in the block.

[1991 318is]

Plug Wires.

Plug wires are $100. It pays to check them. A timing chain tensioner is $65. I'd say replace @ 120,000 miles. It's an easy operation. M42's are great little engines. They'll easily go 250,000 miles or more.

[Stu]

-plugs (get the Bosch '90-'91 M42 specific ones; it's a 2-prong designed only for that motor)
-flush the coolant (block and all)
-air filter
-fuel filter down by the rear tire
-The ignition coils usually last quite some time, doubt you'll need a set
-TCT (you can make one using a V12 tensioner, works great)
-Trans and rearend (Redline is good, but don't put the 'shockproof' in the diff)
-Might as well change the belts too
-Check intake boot, they crack pretty easily on M42's it seems
-Check all the vacuum lines/connections

[asubimmer]

fyi fuel filter is DS infront of the rear tire