Hi! This is my 1st post! My 1999 4Runner has 388,000 miles! Beautiful vehicle I inherited from my brother in law when he passed from cancer. Gonna take it to a million miles, which was his dream.

Has new radiator, water pump, timing belt, and thermostat and complete flush. Mechanic's cannot find why the temp gauge still continues to go to hot, even though no steam or other signs of overheating. Also combustion test shows no head gasket issues. Gauge goes down when heater is turned on.

At times it drives perfectly for 50 miles or so, over hills and curves. Next time it shows hot. I'm sooooo frustrated. Any suggestions would be greatly appreciated. My 4Runner is my baby. 1999 Limited, 2 wheel drive, Fla Georgia truck.....no rust.