Cusser
+1y
I think that should be fine. When one has a gauge (oil pressure, coolant temperature, etc.), what you're really looking for is something that changes from the norm.
Like 3 weeks ago when Mrs. Cusser noticed the coolant temperature gauge on her 2005 Yukon reading significantly higher than ever (she's had it two years). I found that Mr. Water Pump was leaking a little, was down 3/4 of its coolant supply. Since she parks on gravel, there was no physical sign of leakage, and the leak was small, figure it took at least a few weeks to get down to that level where the gauge read high.
But let me say this: without Mrs. Cusser noticing this higher gauge reading (I rarely drive the Yukon, maybe 6 times a year), we would've severely damaged/lost the engine. So I rewarded her. Several times.