93 camry problem
 

first of all my name is jeff, i have a 93 camry with a v-6. the problem i am having is with my cooling system, i have had a pressure check on my system and my cap thats on the radiator pops at about 9 lbs. pressure, i have replaced the cap 3 times but it does the same thing with all of them. every few months my car over heats because i am losing coolant into the over flow tank. anyone else having or have had any problems of this nature? my car has 196,000 miles on it and runs great, i keep good maintenance on it and have replaced the timing belt,all hoses,radiator,thermostat...etc,etc
i also have had a block leak check done

The manual states the radiator minimum opening pressure is 10 psi with a normal around 12-16 psi. Are you using the correct cap?

Does the engine overheat as in the temp gauge goes up or are you just seeing more coolant in the overflow tank? And if the engine overheats when does this happen, in traffic, on the hwy, etc?

im losing coolant and my temp gauge goes up, it usually happens when i am on the freeway, in fact it always happens on the freeway as i do most of my driving on the freeway.