Temp Gauge 'Inconsistent'

[Quinthirty]

Hi,

After changing the oil on my M20B25, I noticed that the temp gauge went lower to the 1/4 mark. This is the first time I've encountered it. It will only go up to the usual temp of 11 'o clock or a few millimeters below the 1/2 mark. But now it seems that even with the traffic and the high temps (90-100s F), I still find it low. I also noticed that sometimes it flicks up and down a bit.

What could be wrong? Any advice would be highly appreciated. Thanks r3v!

[nando]

loose ground nut on the back of the gauge

[KIRIEIW]

loose ground nut on the back of the gauge

Or corrosion forming on the stud of the nut. Clean and tighten by removing the nut and then put it back on after. Be careful not to lose the washer.

[NoM54me]

I just solved this problem in my '86 ES. The two small wires that connect to the back of the cluster by the temp gauge were really loose. Crimped down the connectors, and has been good since.