High Temperature Enigine Fault Light
 

OK, I replaced the valve cover gasket on my 2002 S-Tyoe 4.0 and started getting fault codes for the CATS and DTS system. Soon after I started getting the High Temp Light. It comes and goes. The temp guage will peg then a minute or so later go back down. When replacing gasket I removed the hose from the header tank but no coolant leaked out. The tank is low but wouldn't think this is the problem. Are all these codes coincidental? Any input would be helpful, thanks JKB