yetterben

Ok my oil gauge never worked when i got the car it was pegged. take wire iff goes to zero. Ok so sender is grunding internally and its junk. Got new sender today and nothing still at zero. ground wire again gauge pegs....hmm....gauge works.

I got the asending unit from my local yocal store. Threads are longer same pitch but more of them. Hole is also a pin hole compared to the mazda one. I bench bleed it meaning filling it with oil but nothing. Dont think the hole would have anything to do with it as thats the sender desighn. It is a gp sorensen sender. Any clues other than bad sender????

waysrx7

I thought sending units were made for specific gauges, so if the sender was not made for a mazda 12a then it probably won't be accurate or work. But I would think even with a random sending unit you should have some response on your gauge, so i'm scratching my head too.

yetterben

it is a car specific sender a gp sorensen to be exact from napa.

waysrx7

was the gauge pegged with the keys in but the engine off?
The only other thing it can be is the gauge is broken.

85 FB

Don't think it's your gauge. I'm thinking wiring problem.

waysrx7

The wiring to the gauge is so simple I don't see how it would be the problem given what he said.
connect wire = closed circit and pegged gauge.
disconnect wire = open circuit and 0 gauge.

I'm staring at the wiring diagram and I think I need help to explain how bad wiring would cause this.

EDIT: my bad I way looking at the 1983 wiring diagram, what year is the car?

vipernicus42

iTrader: (4)

The sender has to be specifically made for the car. Usually that means Mazda. It's possible that GP Sorensen makes one, but I don't know what their part number would be for the mazda 12a Oil Pressure sender. Since the wiring seems to be working and the sender shows signs of being different than stock, I'd say it's probably the sender you picked up.

http://www.mazdatrix.com/boil2.htm

Jon

yetterben

yeah its gotta be the sender. wireing works fine. The old sender was internally grounding so the gauge was pegged. When you take the wire off it goes to zero. When you ground the wire it pegs. When i put it on the new sender it does nothing 0.