When driving the car seems to lose power. It does not stall but the tach slowly drops and the suv bucks consistently until the SUV is shutoff and started again. It then runs good for a bit and then starts again.

changes to suv are ...

Bank 2 downstream 02 sensor, bank 1 cat replaced with magnaflow cat and magnaflow exhaust after the Y pipe, MAP sensor, new air filter, oil change, break lines, break bleeder screws and wire repair for the airbag.

Only other problem is when the ignition is on but the suv not started the voltage is about 11.5. When started it goes up to about 14.2 but consistently fluctuates between 14.5 and 13.8 or so. This does not get worse or better when the bucking happens.

any ideas?

 

I got to test drive it and what this feels like is the transmission is disengaging. The tach drops sharp and all power is gone. If you keep it at a steady throttle it comes back but continues its issue. If you give it hard throttle while it feels like the transmission is disengaging it feels like the transmission is getting slammed hard and bad.