I'm not having spark in my spark plugs when cranking, how do you know when its dead?

 

Pull spark plug wires off spark plug end.
Put this open end close to a known good ground point - I typically use the strut tower studs after you pop off the black rubber cover for easy access.
Crank the engine - it helps to have a friend here.
Do you see a spark arcing?
This is how you check the spark by eliminating the spark plug.
Sometimes spark plugs can foul so bad they will not spark.
This procedure will confirm if the coil is sparking okay.



-Ted

 

Can't you also tell if the coils are not functioning/dead by watching the tach while you crank? or does that only pick up for the leading or trailing coil and not both?

I havent heard of anyone here having fried coils.. Usually its always something they didn't hook up right after a rebuild.

 

get a voltmeter and test them.

 

Check spark on all of the wires, it isn't very likely that both coils would fail at the same time.
It could be flooded, or it could need a jump.

It IS possible to have enough charge in the battery to spin the starter and not spark enough (yet still show some spark) to get the engine going.