My 1990 tach needle has rested at 0 rpm for months. Occasionally, it swings back and forth, stopping at 0. The speedometer recently stopped working; the needle parks in the white area. At highway speed it sometimes moves counter-clockwise to around 100 mph, but returns to the white area on slowing down. Yesterday, BOTH gauges starting working correctly AT THE SAME TIME. But this morning both are "dead" again. What is the source of the problem? Loose terminal connection(s) behind instrument panel? Speed sensor? Any advice would be greatly appreciated.

 

I had a similar problem this past summer. I wound up swapping the cluster out with one i got from the wreckers and all was good and at the same time was a good oppotunity to put in some led's.