I have recently had a weird buzzing noise that comes while im driving my rx it will come on and will go off sometimes itll do it just once sometimes it will do it numerous times in a row?? Has anyone had a similar problem???

 

I had a similar problem. If your oil pressure is good, its probably form air in your cooling system

 

should i just drain the coolant and replace?? the add coolant light has come on a few times but most of the time its when the car isnt making the noise and the coolant is completley full

 

It's probably a good idea to do that anyway, when was it last flushed?

Also, make sure that you follow the instructions on properly filling the coolant system as found in the FSM. It can be very hard to get all of the air bubbles out of our coolant systems. Sometimes opening up the heater, and driving around the block a few times with the system fully warmed up (t-stat open) barely gets it all out.

It only takes a small air bubble to get that buzzer going. I've heard it vary from car to car, but if my system has even the tiniest amount of air in it that buzzer is going off.

 

You should check for leaks first.

My car did that, a nd I noticed that was loosing 1 cup of coolant in 60 miles of regular driving , mainly freeway. There was a slight leak where heater hose meets the heater core. hopefully its not my heater core.