What do the 4 prongs in an ignition coil represent?

SOURCE: 1990 Chevy Silverado Pick-up. No spark from the plugs.

How about the MAP SENSOR? Do you check it out?

SOURCE: glow ignitor works, but no flame ignites. ohmed out gas valve coil with wires disconnected = OL is it my coil?

You have a bad flame sensor. Replace it.

SOURCE: ford f-150 ignition coil testing

get them from auto zone change them out one at a time . after each one start up and see if it makes a difference or not . you can always take them back.

SOURCE: Coil and Ignition Module replacement BMW R80 RT

not realy if it runs it runs,,,but if you had looked on
e-bay "there be coils there!" for the bidding its well worth a look if you need parts.. just type in bmw r 80 parts,,,then let loos your wallet!!!

SOURCE: how do you test ignition coil for 01 flhr

Disconnect all wires from the coil. Use a DVOM (Digital Volt Ohm Meter) to test the coil. Connect one meter lead (either one) to one of the small primary terminals on the coil and the other meter lead to the other primary terminal. Set the meter's function switch to OHMS, R x 1. You should read between 2 -3 ohms. Any higher or lower, the coil is probably bad.

Now, you may can remove the spark plug wires from the plugs and insert another set of plugs in the wires. Make sure the plugs are grounded on the heads. Turn the switch on and turn it back off. When you turn the switch back off, you should see a single spark at the plugs.

Good Luck
Steve