2021 5.0 when I get in and just turn the key on the oil pressure gauge goes to the middle without the engine running?.So isn't supposed register after the engine is running?

 

My 5.0 does not do that. Does the gauge cycle on-off when it auto start-stops?

 

i dont think mine does that, i will have to look closer next time

 

i don’t have the auto start/stop feature

 

neither do i, its wonderful

 

I don't mind it with the 5.0, if I had turbos I would feel very differently. The oil gauge drops to zero when it stops, then up again when it starts.

 

Sounds like a bad oil pressure sending unit.

 

mine does not register oil pressure unless the engine is running, just remembered to check

 

The oil pressure sending unit, if it’s the same as 2019 are known to have the potting in the connector failing within the first few thousand miles. But a short condition from oil in the connector would report 0 pressure not “normal” pressure. The dash gauge is more of a on/off on those sensors. My 21 PB does show a sliver of pressure during auto start stop though so maybe it’s changed

 

You are right the sender unit is an on off switch with a resistor built into it. If the switch part of sender is stuck closed the gauge will stay in the center. As long as the ignition is on regardless if it's running or not. Ford hasn't had a real oil pressure gauge since at least the mid 80s.