Thoughts on Alternator diodes

[65comet]

I got a code for the bank 2 cam position sensor. I had bought a new one on the bank one and hadn't gotten around to the bank 2, so I got a new one. Code came back. I swapped 1 for 2 and checked the ground wire had conductivity which was fine. Then I got a misfire on plug 2. Swapped plug 1 and COP into 2 and still got a misfire on 2. Then in researching, I found a Mustang video on their alternators with 4.6L and AC voltage leakage going through high causing unrelated sensor codes and misfires. It said the AC voltage up to .050 to .100 max is allowable depending on who you talk to, and anything higher means the diodes in the alternator are going bad. I checked mine and it was .643 and steady AC voltage with 14.5 DC. The OBD hookup to my laptop said the DC output was 15.5, didn't know if that matters but I thought I should mention it. Since they were talking about a 4.6 engine and alternator, is my number .643 ok for a 5.4 or is it causing my codes and is time for a new alternator?

 

[stamp11127]

Voltage is too high and way to much ac ripple. Electricity doesn't care what engine size is turning the alternator.

http://www.labscopes.com/index_files/Page441.htm

 

[65comet]

Thanks. That is what I thought but I wanted some confirmation. I just wanted to make sure the alternating current reading was all vehicles or if it would vary by make/model and type of alternator with this reading being normal for an Expedition. I never had one do this before(that I can remember) to have to investigate what was happening. Either the alternator worked or they didn't charge or bearings went bad and I got a new alternator. I may have known this in the past, but I got a brain injury a year and a half ago and a part of it died. Some things in my memory are just gone.