The guage dont show any movement unless the day is really hot, could it be my thermostat sticking open??? and the oil pressure has dropped to 30 at highway speed . Sender??? I switched to 20/50 oil????

 

You should know the condition of your thermostat if you are even driving a rex. Nuff said there.

Oil pressure varies with RPM, not speed of car. See thread below:
https://www.rx7club.com/1st-generation-specific-1979-1985-18/fluctuating-oil-pressure-442161/

 

Highway speed should be around 3000 RPMs in 5th gear, so you should still have around 60 PSI of oil pressure. I would start by checking the sender, they go bad.

The temp gauge should be fairly solid once started and warmed up, it shouldnt fluctuate too much at all. As a matter of fact, I would be more worried if mine did than if it didnt.

~T.J.

 

Mine Hangs At Thirty Pounds Steady, But It Dropped From 60 To This Point Should It Not Go Back Up, What Do I Do?????????

 

Check the connection at the sending unit. As I said in my FIRST post, the sending unit could be bad, they die on these cars commonly after so many years of use.

~T.J.