The car is a '99 C230k with 69k on the clock. It wont start at all now after a period of running rough at times. I have a few questions I need answered because I don't have the manual. Here goes?

Are Autolite platnum spark plugs okay to use in this car? Or should I stick with the Bosh?

Plug wire resistance is 2.05 at 20k setting, is that okay?

What should the spark plug gap be?

On the fuel filter, what side does the metal seam go on when looking at the car from the back? I forgot which way it is supposed to go.

If I crack the nut on the return line in the enfine compartment, should fuel come out when I crank the engine? If so how much?

There is a small amount of brown goo that looks like oil pooled next to the third plug back from the front of the motor, what's up with that?

Could this be the problem described here regarding the Air Mass Meter (Mass Air Flow sensor)?

http://www.peachparts.com/shopforum/showthread.php?t=124658&highlight=c230+plug+wires

That's all I can think of to ask, thanks in advance...

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1984 300TD
1983 300D
2002 Chevy 2500HD Diesel
1995 Dodge 12 valve Cummins Dually
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