Michail

Hi. I'm a bit confused.

I have this problem where my oil pressure gauge has slammed into the top and refuse to go down, except during rare conditions where it decide to temporarily slam into the bottom instead.

Searching for clues online it seems like my LG4 supposedly has:
- One "oil pressure switch"
- One "oil pressure sender"
- and perhaps also an "oil pressure sensor"?

Now, what is what and which one is which, and why?

There was a big bulbuos thing on the driver side of the distributor that I replaced. That didn't change anything.

BigBadLou

iTrader: (3)

A "sender" meanst the same as a "sensor". It is the one that senses the oil pressure and sends the signal to your gauge.

If your gauge is pegged to the right, it's most likely a bad connection on the sender (or on the back of your gauge). If it goes down to 0, it might be a short in the circuit.
If none of the above is true, it could be the sensor/sender.

Btw, only Trans Ams had an oil pressure "switch" on the carbed engines, supposedly. But that has nothing to do with your gauge so you can ignore it, don't let it confuse you.

Hope this helps.
Lou

Michail

Thanks, I guess I have a short somewhere from what it seems.

Just to clarify, can you tell me if these statements are true or false?

- A carbed '86 LG4 has no sensor down by the oil filter.

- The sensor is a bell-shaped cylinder residing next to the distributor. It is screwed to an L-shaped pipe which connects to the engine almost beneath the protruding mushroom underside of the distributor.

- It has one tan wire connected to it.

BigBadLou

iTrader: (3)

I am no expert on pre-89 engines but from what I've gathered over the years, I'd answer true to all three questions.
I don't think I'm wrong but if I am, somebody please correct me.

If you disconnect the tan wire from the sensor, the gauge should read full. If you ground the wire (on the block or somewhere), it should read 0. With the key on, of course. If the readings are different, it would be a wiring or gauge issue.

Hope this helps.
Lou

Michail

> If you disconnect the tan wire from the sensor, the gauge should read full. If
> you ground the wire (on the block or somewhere), it should read 0.

VERY interesting. Thanks a lot! I'm gonna check this soon.