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Ohm meter dirty tricks

Started by ndd · Mar 8, 2018 · 4postsSMF 2010–26

nddMar 8, 2018, 9:11 pm · #1

Oh the fun of being stranded with a no start condition after buying new shoes! Helps with walking ha!  The 302 started good to go to work then shoe store. Get to car cranks no fire.  Sat in parking lot all night.  Get back next day starts and drives home great.  At home get the trusty volt meter out find pick upcoil in distributor out of range.  Replace distributor. Starts up well. Car runs well. Drive a bit shut off. Will not start after short period at all no spark ugh!  Have towed home!   Get voltmeter out again!  Coil ohms out plugs wires distributor rotor cap new!! What the heck is wrong. In the end it was the coil primary and secondary ohmed corrrctly.  So I will say I was misled. My car has ford distributor to a gm hei 4 pin to a Nissan coil.  Now back up with a MSD blaster 2 runs great again.  I am hvac guy and use voltmeter well weird how coil tested well but was bad!  Long live the s12!  PEACE

T a

JonBMar 8, 2018, 10:08 pm · #2

Ive had a coil test good, but when running, burn an arc right through the plastic to the terminal. Not until it melted mor plastic and I saw smoke did I know what it was. Collossal headache.

Took it to a few shops even - didnt help.

Took some electronics classes since then, but still dont know that I would find that specific problem easier.

Lesson learned towards ignition mods really. Same like you can shorten the life of a motor making more power; you can shorten the life of all the ignition components with amps and boosters

SkeeterApr 3, 2018, 4:36 pm · #3

OEM coils can be tricky as most manufacturers don't post service specs for them. Had coil issues with my 96 Sierra. OE spec only showed readings for ambient temp of 70 degrees, but once it heated up to operational temp of ~190 and above, the coil would fail intermittently. Drove me nuts for about a week, then I broke down and chose to get a new one. PITA.

weitrhinoApr 4, 2018, 4:21 pm · #4

I've had hairline cracks in a coil case that only arced in the rain. A good test is to spray a water mist at the running coil and look for the short, in the dark if possible.