So, the gauges on my '83 seem to vary wildly, in particular the temp and oil press. I'm wondering how much confidence I should put into them.
Upon taking delivery of the car, it was a 3 hour drive home. The temp gauge stayed on the upper end of the limit. The forst 30 mins it looked to be over heating but when I pulled over it all seemed fine. So I continued. The gauge was at 75% about 90% of the time. going up hills at time it was maxing out, but then would settle down. The car really didn't seem to be overheating at all. How much can I trust these gauges? Any experience? The oil press gauge bottoms out when I'm at atraffic light but is fine driving.
The car made it home fine on a 3 hour drive. What does this tell us?
The factory gauges, they are over 35 years old, that's like 245 in dog years, are kinda suspect, mostly connections, old crusty wires, you get the idea, are
It also is dependent on condition of the engine and cooling system,
Get some mechanical gauges and mount them (temporarily if needed) so you can compare the two.
Fox body cars are known to do this. It may be a ground, the capacitor for the fuel gauge in some years, or a Gremlin. I had a 79 Mustang and a 87 Cougar that responded to a good tap to the dash above the right knee when the gauges were pegging out.
Extra gauges are good.