Four wire COP current ramp

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Darren Fraser
OneWave
OneWave
Posts: 25
Joined: Sat Jul 18, 2020 7:45 am

Four wire COP current ramp

Post by Darren Fraser »

Hi guys
I had a classic shorting primary wave form on cylnder three
on a 1az engine in a 2010 Toyota Noah today. Current went
straight up to 3 amps before starting to ramp up to 10 amps.
Swapped the coil with cylinder number one and the "shorting
primary" stayed in cylinder three. I measured the current on
the earth wire on all four cylinders and checked ign
voltage, IGF and IGT on all four cylinders which showed
identical wave forms. Has anyone come across this before?
Cylinders 1,2 & 4 give a really good current ramp wave form
but cyl 3 gives a 1/3 vertical line before the ramp no
matter which coil is used. I can't think of anything else
that would do this apart from a shorting primary?

vasek
TwoWaves
TwoWaves
Posts: 57
Joined: Tue Feb 17, 2015 7:27 pm

Re: Four wire COP current ramp

Post by vasek »

Hi.
Need - the file with IGT,IGF,CURRENT.
It would be nice to see this exciting Thriller.
It's like in the new C.J.J.Nolan movie.
Everyone runs somewhere with a very significant view,but - backwards.))

Darren Fraser
OneWave
OneWave
Posts: 25
Joined: Sat Jul 18, 2020 7:45 am

Re: Four wire COP current ramp

Post by Darren Fraser »

Can't upload psd files yet from our old lady, I'll try and upload the Pico 6 software today. I'm also going to try and find the common ground or ignition to get all for ramps on one page.

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Autonerdz
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Location: Washington State USA
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Re: Four wire COP current ramp

Post by Autonerdz »

I can't think of anything else
that would do this apart from a shorting primary?
While what you describe can be caused by a shorted primary, it often is not. Many things inside and outside the coil can cause the coil charging current to rise abnormally fast.
One of these things can be as simple as a fouled spark plug.

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