2001 Ford Expedition 5.4 triton 2 valve with 218k on it.

I have a weird issue with my expedition, intermittently the speedometer will go flat and the transmission will jump out gear and
I coast to the emergency lane to where I wait 10 minutes or so and I can start her back up and she will go again for a little bit or
take me straight home. I changed the upstream oxygen sensors as the right one was shorting out on the exhaust manifold. then
i found that my MAF sensor was not reading right so I changed that out too. the SUV seems shaky at idle and flooring the gas
pedal it seems it wants to but is not giving it. When I move the wire bundle from the PCM I can hear the RPMS move to 1500rpm
and I see my voltmeter on the TPMS sensor 5v drop from 5 to 4.8 and sometimes just 0volts but then comes back to either 4.8 or 5v
again. all grounds to PCM are good and I measure 12 volts on the PCM for 5v reference.

Could the shorted Oxygen sensor mess up the PCM ? all the pins are clean and on the connector it all seems fine too.

Any help would be appreciated.

the speedometer will go flat and the transmission will jump out gear and
I coast to the emergency lane to where I wait 10 minutes or so and I can start her back up

Does the engine die when the speedometer goes flat?

all grounds to PCM are good and I measure 12 volts on the PCM for 5v reference.

You have 12 volts on the 5v reference?
What method are you using to check PCM grounds?

I replaced Pcm and fixed the problem.