Mazda Miata: 97 oil press. gauge

I know that the oil pressure gauge is a fake and is in reality just an
analog idiot light, but how can it still read normal oil pressure with
the sender unit wire disconnected from the sender unit? If the sender
unit grounds the wire with normal a oil pressure condition, then a
disconnected sender unit will not ground and shouldn't the "gauge"
then read zero oil pressure? Mine is totally unaffected by
disconnecting the sender wire, still reads the same normal prss.
with or with out the sender unit were attached.
Thanks,
Mike

Sure you would, if the sender failed (I.e. failed to detect oil pressure and
open the switch), or if the wiring circuit opened, you'd see "oil pressure"
with the key on/engine off...

-cliff-

"mcola" <att-spam-.net> wrote in message
news:tJSuc.16786$ops.worldnet.att.net... 
it's 
if 
zero.