Hi secondary voltage

Hey guys I am working on a 05 Ford escape V6 3.0. I diagnosed a bad coil and the misfire went away but my question is the primary voltage spike is +400 volts!! I am positive I have my setting correct on the pico. I am using a 10-1 attenuator and set on highest voltage and still going past 400V is that normal? I am guessing not since I have looked at other waveforms and its less than 100V. It is on cyl 4,5,and 6 I have not checked the back one yet. Number 4 is the coil I changed. I just double checked my setting with the attenuator and I am reading battery voltage so the setting are 100% correct, trust me that is the first thing that I thought of.
Will that have a negative effect on the ecu or will it be ok?
thanks for the help

Secondary should be over 10kv I don't think it would run if you only had 400v I have to believe your settings are wrong but I don't have a Pico to tell you want they should be

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Is it all three front coils that are showing high primary voltage? Or, just the one you replaced?

Very unusual. I've checked primary voltage on those coils, and never seen one go above 300V.

Check the condition of the spark plug excessive gap drives the secondary and primary voltages through the roof. or you could have a coil in which insulation has broken down the secondary and has an arcing short to the primary,

Oh wow somehow I missed that your question said primary. I read the topic and apparently had in my mind it was secondary! 400 is way high for primary!

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I didn't check the spark plug gap but customer put new plugs in the front bank. The engine runs and idles great so I am thinking if it were gapped to far or bad plugs that is driving the voltage spikes through the roof it would be misfiring and its all 3 in the front. #4 coil is new and its also 400+ volts.
The customer came and seen it was running good and took it against my advise but I still want to figure this out so the ecm don't get fryed

Just a thought - The ignition capacitor? Usually bolts to the right engine mount on these. Would a problem with that cause high primary voltage? :huh:

Tyler.. I was talking to Scanner Danner's brother yesterday and he had the same thought about the cap. But I thought the capacitor was just for radio noise, but who knows I guess anything is possible. Now that I am thinking about it when I changed the battery and started it up, the radio cam on and was making some crazy sound, at the time I just turned it down and never gave it a second thought!
I bet the cap is burned out.. its funny how getting some sleep can refresh your mind. I am getting it back Tue or Wed. I will let yinz know what I find.
Thanks for the help guys.

I did a test with a spark gap tester just see what voltage a coil primary can kit out and still produce a strong spark on the secondary I was a bit surprised this is pushing the spark gap to the max with peak detect turned on. 1.6kV

I was just discussing the capacitor function regarding a Lincoln MKX with a tech at another garage.

His was melting coils on one of the front cylinders and he saw the capacitors on the diagram and was wondering if they could have had anything to do with it.

I'm interested to see what you find regarding the capacitors if you get the car back in your bday.

(The Lincoln ended up with a bad PCM, keeping one coil grounded forever).

This is a more sensible test run the air gap wasn't that huge using the x10 attenuator as I broke the x100 and the scope hasn't an x20 scale.
Cursor Reading 360v but it fired the trigger set to 400v

I will definitely follow up with what I find.