67 390 temp prob
 

My temp guage is up & down and all over the place as I turn, accelerate and level out speed. I think my thermostat may be buggered. Any ideas pls? Even if shows high, does not seem to be boiling, drops as quick as it goes up. Level constant driving is normal temp, but goes up when turn or accelerate, then levels out again.

Re: 67 390 temp prob
 

Sounds like you have a wire that is grounding out...

Check the wire that runs from the engine to the dash.

Also be sure that the connection to the water temp sender is clean and a tight fit.