badwithcomputer

I had the option or Race Red or Sporty Yellow but I just went with black. Probably gave up a few horse power

DemShinyNutz

You can test resistance between the new and an old to get a idea

badwithcomputer

Excellent! I'll give that a try!

Summers22

iTrader: (2)

I laugh when people say, "my truck is mis-firing, I used ebay COP's, what could be wrong?".....

Martian

It's a valid question. That's only one part of the equation. As you know, the cheap Chinese coils have been in my truck for two and a half years now with no hiccups.

redfishtd

I worked in Utilities on transformers up to 750 kv and a resistance check is okay but far from a good one .
Turn to turn shorts are very difficult to deal with and testing at some lower voltage is iffy being the charging draw is high . Basically we did a watts loss test that gave us an idea of the state of the insulators . I had the protection end of the job to detect problems when energized at full volts it had to come out of there within cycles if bad .
I would love to know exactly what is failing on these bad cops . Are they burning open with the load or shorting out internally ,do they have internal protection ?. An open can be found with a meter unless its intermittent . I only had one bad one and I tossed it .
I guess we could build an electronic tester but you have to be careful with 50kv output .
Maybe someone here has done some testing and cut some open .

badwithcomputer

Good lord that was technical! I can switch my multimeter to DC and AC and that's about it lol

badwithcomputer

Just a small update, my check engine light went out, truck has been running great. My avg liter per 100 has dropped from 18.6 to 17.4. Everything seems well...for now.