While driving uphill with the AC on, my temp gauge pegs out. Turn the AC off, and the temp cools down. While drving on a flat road with the AC on, it's fine. About a year ago I had the radiator flushed and filled and I know this doesn't totally clean it out. So.... could it be one or the other or both?

I appreciate the input.

Also, is there a high flow radiator that may fit the VX?

Thanks in advance.