Oil sending unit wiring help

[echelonwarrior]

Okay so I have both the stock and aftermarket oil sending unit on a remote line coming off the back off the block from the oem location the aftermarket sending unit is one of the gold bell ones it has two posts one says G and the other WK I've read the G is for gauge and WK is for the idiot light. My gauge was working fine before then somehow the wires came loose. I think I had it wired as wk was to the gauge and g was ground turned the car on and it pegged 100psi of oil pressure swapped the wires and it did the same thing but when I swapped them and turned car to accessory the gauge went nuts ready 10 50 20 90 100 60 psi so I'm wondering
1) does this thing not need to be grounded and
2) does the immediate peg of 100psi sound like a wiring issue or bad sending unit?

[DPancoast]

When I had that issue with my old mr2 (was fine, then tried to wire it in to dim.... Ended up changing my oil pressure as I turned the dimmer lol), it was a bad sending unit.

However what kind of gauge is it? Does it have a key on ceremony?

[echelonwarrior]

Idk what you mean by key but the gauges are prosport the sending unit is generic

[DPancoast]

When I click my key to the II position my needles swoop to max, down to 0 (or -30hg) and then back to 0.

But anyway, I'd suspect a bad unit if the wires got crossed

[echelonwarrior]

Yeah I'm thinking bad unit