I rented a pressure tester from Autozone I want to check the coolant system for any leaks this my first time doing this on my 2004 RX330 could someone tell me how much pressure do I pump it up to?
Never mind I found out the tool I rented isn't small enough to fit the radiator. I will have my mechanic look at it.

 

I rented a different pressure tester that has many different size adapters to fit the radiator.
I still need to know how many PSI do I pressure it to?

 

Radiator caps keep the pressure at 14 - 15 pounds. For leak detection, pump up the pressure to 30 pounds.

 

Thanks for the pressure information. I see a slight leak coming from the radiator tempted to pour that stop leak stuff in but not sure what effect that has on other components. I currently have 95K miles I would like to make it to at least 160K.

 

Don't use that stuff. You should fix the leak properly or you'll just have more problems later. You don't want your cooling system blowing up unexpectedly.