Driving down the road this morning, I suddenly noticed that the electrical gauge on my 1987 Grand Wagoneer had pegged at "18". It also appeared that the water temp gauge was reading a few degrees higher than normal. After awhile, the temp gauge and electrical gauge both returned to normal, with the electrical gauge reading below the red band, i.e., about 13.5. Later it went to the high end of the red band again, and subsequently returned to "normal".
Is this merely transient instrument flucuations, or something genuinely needing attention?
Any suggestions on what is causing this will be appreciated.