Temp gauge going up with RPM?

[njsteve]

It means you're driving a Mopar. They all do that.

If it's not a Mopar, you probably need a better ground from the block to firewall and block to subframe. Also the voltage limiter in the dash may be bad (I know Mopars use one, don't know about GM, though)

(This is one of the reasons I went to a SW mechanical temp gauge with a capillary tube on my Charger. While the mech gauge reads 165 degrees at full warmup and cruising, the factory electrical dash gauge says 200+ and rising...til I stop at a light and it drops back down.)