The oil pressure gauge is fed a steady signal by a microcomputer that appears to be within the instrument cluster. If we can get access to the input of this gauge, we should be able to make it read actual oil pressure by exchanging the pressure transducer with a variable output device, and designing a signal conditioning circuit to interface the transducer signal to the gauge.

We need to know if the gauge inputs are accessible, and how the gauge responds to inputs over its whole range. We also need a source of pressure tranducers. Does anyone currently have their instrument cluster out that can take a look at getting some of this information?

 

I have been very close to buying a cluster to look into this.

https://www.rx8club.com/series-i-tech-garage-22/making-oil-pressure-gauge-into-true-gauge-8767/

 

Never saw that post by POOMan. If you do get that cluster, could you also look at the coolant temperature and tachometer gauges. It would be useful to hook in a beeper to immediately draw your attention to an overheated condition, and exceeding a pre-set speed (indirectly through the tach, unless the input to the speedometer is actually analog)

 

I recall that over on Miata Net they had a way to make the oil pressure "dummy" gauge read actual pressures. I believe that it involved replacing the sensor on the engine only. Not sure if the same would work for the 8, never got around to doing it on my wife's Miata either. But if the sensor is the same, you may be able to find where to get it over there.

 

http://www.miata.net/garage/opg.html

This is probably what you mean. But in that case the replacement gauge must already have the capability of accepting the signal from the replacement sending unit.

 

That is one of them, if you go into the garage there are actually a few more ranging from the NA models through the NBs. A bit more complicated than I remembered and some of the gauges would accept the signal but it was only relative because they weren't actually calibrated. Certainly it would be a lot more complicated in the 8

 

This seems like a worthwhile project. Was there ever any progress made here?

 

bump for a good idea!

 

no ****!

 

1999-2005 Miata fix that works and turns the oil pressure gauge into a REAL gauge.

Website with the fix

http://www.mazda-speed.com/faq/opg/

Youtube that show that it works

www.youtube.com/watch?v=aTWvl2_5zoo

 

The Miata's oil pressure guage is already a real/functioning gauge, though. The mod above just makes it more responsive.

 

This is something that I would love to do to my car... damn useless oil pressure gauge!

 

The oil pressure info is sent via CAN to the cluster.
The gauge is a surface mount, non-proportional electromagnetic indicator.
The only way to do this would be to gut that section of the cluster and mount a real, proportional driver and wire it to a linear sender.

Thanks but no thanks.

 

so there is no hope for getting the gauge to work?

 

Never say never

 

Has anyone ever asked Mazda why they sold a car with an oil gauge that doesn't work? When I asked my dealership they told me it did work..... If enough ppl complain maybe they will do something, or at least give an answer.

Kinda of like my Ipod adapter won't work with XM Sat.... Mazda doesn't have a part, I can buy one for $200 though.

 

The theory behind dummy gauges is that its a selling point that they have them, but since its just a dummy gauge they don't have to worry about people bringing in the car because the oil pressure is a few ticks off from where it usually is. You would think that on a "flagship sports car" the gauges would be functional...but then again that would make sense and we can't have thinks making sense otherwise the whole system will collapse in on itself...