Engine Temp Gauge Problem

[miksax]

Two days ago I forgot to turn off my lights in my 91 LX. The car was completely dead and I had it jumped. Ever since that moment the temperature gauge has been acting strang. When the car gets to operating temperature the needle moves up and down a notch on the gauge when driving, sitting at a light, or just parked. It never did this before--could this problem and having the car jumped be related? Or does it sound like symptoms of an issue that you've had with your car?

Thanks

 

[jrichker]

Is the volts gauge moving at the same time?

How is the ground on the engine to firewall?
The secondary power ground is between the back of the
intake manifold and the driver's side firewall. It is often missing or
loose. It supplies ground for the alternator, A/C compressor
clutch and other electrical accessories such as the gauges.
Any car that has a 3G or high output current alternator needs
a 4 gauge ground wire running from the block to the chassis
ground where the battery pigtail ground connects.
The 3G has a 130 amp capacity, so you wire the power side
with 4 gauge wire. It stands to reason that the ground side
handles just a much current, so it needs to be 4 gauge too.