I've had an issue with my 06 GXP coolant temp gauge randomly bottoming out and jumping to beyond hot for about 4 months now. It does it randomly, then returns to normal temperature readings. I've flushed the coolant, replaced the temp sensor and thermostat, and back traced the pins from the temp sensor to the PCM. All of these things seem to be fine, but I still cant track down my issue. I don't know if it's related but the only time the horn has worked in the entire time I've owned the car was for a random week where I was having no electrical issues. This leads me to believe it must be something ground related but I can't figure out where any of the grounds go on the car. I hit a point where I decided to ignore the issue, but now that it's getting hotter outside the "A/C off for engine safety" is really starting to get on my nerves. Any suggestions, help, or ideas would be greatly appreciated.
