When going fast-ish temp gauge moves between 80 & 90 Deg C

[Fixanything]

Is this normal, when going a bit fast-ish temp needle moves fast (few seconds) between 80 & 90, when I slow down a bit to 65 ish the needle is steady at just under 90, not noticed it before. No other symptoms, car drives perfectly.

[jay964rs]

When my 2002 2.5 was on a dyno recently, the temp gauge said 100 degrees, but with the laptop plugged in, the water temp was apparently 83. Not 100% sure the gauge is accurate.

[Fixanything]

Jay,

I'm not sure its faulty, as it just may be I've never noticed it before as the temp gauge is masked a little by my hand/steering wheel. To be clear, the temp never goes above 90 and appears to drop to 80 and back up to 90 cycles)when I'm going faster than 65 mph, it does this (cycles 90-80-88~90) within a few seconds and is consistent i.e. never going below 80 never above 90, could it be that it is actually detecting the thermostate opening and closing and/or cooler coolant as more air is forced through the radiator at higher speeds.

Cheers
Mark T

[Adrian W]

I think it may be your imagination, either that of the gauge is bumping about a bit, the ECU makes the gauge read 90ish when warm, if there is a problem it will go full deflection. this is how it was designed,it might as well have been a light.