This might be normal, but i am not sure...

something is not right with my car's power, and i am suspecting a grounding issue......

engine rpm at idle appears to be affected by power draw....for example, opening or closing windows will cause dips in rpm. turning AC on will cause a dip in rpm, oil pressure guage (new) fluctuates with power draw (become jumpy when ac is on).....I changed the voltage regulator with new Bosch unit, but still having a problem. tested battery and charging system at Autozone, they told me all is normal......


is this normal behavior? or are these unrelated issues?

thanks,

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1993 300E, 2.8 M104 .....