Red oil light troubleshooting

[NewVanOwner]

Van: 1987 Cargo, new acquisition.

Red oil pressure light started coming on today. The cluster has no gauge, just the light.
The light was coming on at idle (either stopped or coasting). It would go off when revving.

I disconnected the wire from the sensor located on the silver assembly which the oil filter screws onto. The sensor as a blade connector, and basically looks like this:

https://i.imgur.com/EjJGy9i.jpg

The oil light still comes on at idle. And, it still goes off when revving. Assuming I am disconnecting the right wire, what could account for it turning off when revving?

Autozone also spec'd for a possible sensor that looks like this:

https://i.imgur.com/6NpauIH.jpg

Is there another oil pressure input somewhere?

Thanks for any thoughts/help.

[Burntboot]

The top picture is correct for your van, the lower one is for van's with an oil gauge.

As to your light, there are 2 devices which can activate the oil-light in the dash.
The sender by the oil filter and the level sensor in the pan.

You'll need to diagnose wether it is an actual pressure problem, level problem or wiring for either/both.

Given that its new to you, first order of business would be an oil change.
It calls for 10w30 or 10w40 for most climates and if some well meaning person filled it with say 0w20 that could cause low pressure at idle.

Welcome to the party!