My MX5 NC 3,0 nearly always shows low water temperature on the dash gauge.
In the past with other models I thought this might be a sticking thermostat.
Not sure here. Fairly new to the car. Only had since May/June.
Any ideas?
Cheers guys
Del
Does the heater burn your feet? Does it take a while to blow heat out?
Do you own or can you borrow an OBD scanner tool as this will tell you the exact water temperature.
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It should (the gauge) just be slightly below the halfway mark and never move.
As above the heater should be toasty and gauge this weather should reach the mark as described pretty quickly. More often than not on a car 10 + years old it will be the stat at fault.
“It should (the gauge) just be slightly below the halfway mark and never move”
Same with my 12-plate. I queried it when I first had my car.
I stand to be corrected but if it does turn out that the water temperature is low get it sorted because the oil temp will also be low. On early mark 3’s in particular this might end up being expensive.
And here’s the instructions 
Bit of a fiddly job and took me around 3 hours.
I found that looking from the top, you can get half an eyeball on the ‘invisible’ bolt above the smaller hose to locate the socket and I found undoing that one last was best so I could lift the old thermostat away with the socket still on the bolt, so no chance of the bolt dropping into the depths.
You’ll also need FL22 coolant to refill and need to ‘burp’ the system afterwards.
There are a few threads on this if you search back. The thermostats (including mine) fail on an NC around 70,000 miles.
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Thanks guys for all that. Appreciated. I was afrraid of that. Yes I’ve got some FL22 already so no issues there.
My gauge is well down most of the time and only ever gets to a quarter way up.
This is the thread I was looking for :
Cheers Andy.
Thanks for that bud.
Del
Does anyone know where there is stock of the Mahle TI 202 82 Thermostat ?
Every listing I have looked at seems to be out of stock.
Look at the Autolink one, I know it’s not Mahle but should be a decent replacement.
Cheers Mick - I fitted a borg & beck aftermarket one a while back and it seems to take a long time to get up to temp.
Other 2.0 mk3’s I have been in seem to get up to temp much quicker.
I thought that I would move to the Mahle or even an OEM thermostat on the basis that the engine coming up to temp so slowly is generally not good for engine wear or the oil.
I have a 2.0 mk3. My temperature gauge usually sits around the 4pm position. Today with it being rather fresh was at the 5pm position. Still nice and toasty with the roof down.
I’ve fitted the Mahle stat too, that was in my previous NC, all good
I know it’s been a while since fitting yours, they tend to get air locks when refilled, can’t be that though. Probably try another, presume that’s why you are searching?
Don’t think its air in system - the heater gets nice and toasty and the temp gauge still gets to the 4pm area ( eventually ) - just seems to take more time than expected to do it.
My mates 2.0 NC is up to temp much quicker than mine.
Temp gauge still gets to the 4pm mark on the gauge - even today when it was much colder.
It just seems to take a long time to get there.
Cheers Mick - pretty much the same as my mates 2.0se
Mine is taking much longer than that - probably 20+ mins which I feel is way too long.
On a side note - the thermostat in the car may not be what I thought.
Apparently Mahle stats carry a bar code - this does not have one !!
A stat change I reckon then.
Re-configured my torque app on the head unit and went for a run.
Coolant barely getting to 65c when moving ( 40 mins drive )
Got home and sat on the drive - coolant does get to 90c and the fan kicks in.
Deffo a thermostat issue - guessing it is stuck slightly open.
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