Is it normal for the voltage to drop about 1 volt from 13.1 to about 12.1 during high rpm operation?

As a side note, if I disconnect the battery while the car is running, the car does not want to run above 2000 RPM. At 2K, it's as if you hit a rev limiter with the car bucking.

Is this an indication of an alternator going ?

Thanks,
Ben

 

Do not disconnect the battery while the car is running. That's a good way to ruin a good alternator.

Where are you taking your readings?

 

disconnecting has been accidental but wanted to relay the results of what happened.

I am taking readings through the PCM and logged via datamaster.

 

I think it is fairly normal to see this (though it may not be the best thing). Seems like I have seen previous threads with the same question. There seems to be some common voltage loss through the ignition switch or it's connection.

 

I wanted this question to stand alone. Well, sounds like I can eliminate this as a possible problem.