eccles

Early Miatas had functioning oil pressure gauges that fluctuated with the rise and fall of the oil pressure. However, the "gauge" in later Miatas is simply a glorified idiot light, with two positions: rock steady at about half-scale whenever the engine has anything more than a couple of psi of oil pressure, or Zero when it doesn't. If it ever moves while you're driving, you'd better kill the engine immediately.

I understand that Mazda made the change because they were getting too many service requests from ignorant owners who were concerned by the fluctuations of the genuine gauge!

One would hope that they consider the target market for the RX-8 to be a tad more mechanically-savvy, but does anyone know for sure if the OPG is actually functional?

Sputnik

Actually, I would think that a "sports sedan" type car would have less mechanically savvy owners than the Miata. I wouldn't count on it.

---jps

3Rotor

I have never even sat in a Miata, but I can tell you that in an RX-7 the Oil Pressure Gauge does rise and fall with the RPMs (as it is designed to do), the gauge in the RX-7 became less and less accurate as the car became older. It is an easy fix and was generally due to dirt, grime and oil residue on the Oil Pressure Sensor which is located just below the oil filter. Therefore it was prone to have a drip here and there fall on it as the oil was changed.

bwayout

I hope it's real!

eccles

Unfortunately, the Best Motoring and C&DTV clips seem to confirm my suspicion that it's an "idiot gauge." Note how the needle immediately springs to a little over half-scale as soon as the engine is started, and never wavers from that point even when the throttle is blipped to 7000rpm. This is exactly the same behaviour as the fake gauge in recent Miatas.

maxcooper

The water temp gauge was non-linear on the FD RX-7. From about 150F to almost 250F it just sits in the middle. Someone in the San Diego RX-7 club figured out how to make it linear again with some minor changes in the electronics.

I hope the RX-8 has a linear gauge from the factory, but there may be hope for re-linearizing it if not.

-Max