2007 NC 2.0 Coolant Temp and Oil Pressure Gauge Readings Heads Up - They Really are Pants - Beware!

Technical Area Engine, Transmission, Exhaust etc
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  1. My model of MX-5 is: 2007 NC 2.0 Sport
  2. I’m based near: Blackpool

I have completed a test modification to install real coolant temperature and oil pressure gauges together with coolant overheat and low oil pressure warning lights. I also now have a radiator fan running indicator light.

After doing this and checking coolant temp readings with an OBD I can honestly say the standard “pretend” gauges are pants and probably cause more problems than they cure.

My coolant temperature changes up and down above 80 degrees more than the factory gauge shows and the factory gauge gets nowhere near the top quadrant when the fan kicks in at 100 degrees, it pretty much stays in the middle once running temp is reached.

My oil pressure fluctuates nowhere near as much as the factory gauge indicates.

There are no proper scales on the the factory gauges and so they just do not give us any decent information or warning of impending doom. Even if you do not want to go down the real gauge route I would definitely recommend warning lights for low oil pressure and high coolant temperature.

I am guessing this is why we hear stories of “weaknesses” in our engines when they fail through overheating or low oil pressure. We simply do not have proper warning that something is going wrong.

Why oh why would Mazda compromise the car like this?

Don’t get me wrong, I still love the car and now actually drive it a bit harder and with more frivolity than before :grinning_face: . Just wanted to get this out there.

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I’m guessing you’re new to NC ownership ? Everything you describe about gauge readings is very common knowledge.

Google Rotarytronics for something that actually works, properly.

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Thanks for the note.

I was generally aware of the pretend gauge problems from reading all the good info on here. I just didn’t realise I how useless they were. I did look at the Rotarytronics system but it seemed really complicated and filled with risk when installing it. I have gone for a much more simple (and cheaper!) solution. My low oil pressure warning switch is actually the <6psi Lucas one fitted to cars from the 50/60s. :slight_smile:

Still the most fun per pound car I have ever owned :+1: