The KJ's temp gauge is a dummy gauge,at the 1/2 mark the coolant is between 178 degrees and 229 degrees.
Check water pump impeller(plastic and wrong coolant can eat it),coolant leaks,bad cap,and electric fan operation.
I'd second that! I had crappy heat when my cap wasn't sealing. If you haven't changed it in a while might be worth a shot. They don't last forever. May benefit from a system pressure test too. WP isn't hard to check either, just get a new "gasket" before you start if you do. It's a big O-ring sort of crush gasket and really a single use item.
Also, maybe for you the coolant got low enough to get air in there. The sensor sits pretty high and may be in an air pocket thereby not giving a true reading. You may have high temp but the gauge doesn't know it and you need to burp the system.
As for where the coolant went... Not to alarm you too much but make sure you haven't "created oil" :icon_eek:
That is, it hasn't mysteriously increased in volume. When mine overheated in traffic it blew the HG and went into the oil. I didn't even spike the temp gauge. Went about 2/3 of the way but I did get a CEL for the fan relay as it was happening. That is the only time I've ever seen it read anything other than 1/2.
Just some thing to think/worry about :uhoh2:
