This is due to a vacuum leak as the canister dissent build up the correct pressure. If it hasn't happened to you if the pressure gets to low you will lose almost all of your breaks and your power steering as,this pressure is what gives you the added power reserve you need in this vehicle. It astounds me that no one has the correct information and can let people know this, I found out by dum luck and the lose of brakeimg power to find out. Good luck

 

The brakes are boosted by a vacuum that is created by the engine running. A large enough loss of vacuum will make it harder to stop the vehicle, but it will also adversely affect the performance of the engine, and if it is bad enough the engine will not even run.
The power steering is boosted by a pump pushing hydraulic fluid through the system, and will only lose that boost if the engine shuts down, or if the power steering pump stops working.

If there is a bad enough vacuum leak to adversely affect the running of the engine, it can also have a slight impact on the performance of the power steering pump, causing a reduction in power steering performance.
In both cases, if the engine shuts down, you will lose power assist for brakes and steering. That has been a well known and established fact for many decades and was even taught to us in drivers ed in high school.


You should not drive a car that has a vacuum leak bad enough to affect the performance of the engine, as the engine could shut down without any warning, and not restart.
Also, running the car with a vacuum leak could thin out the air-fuel mixture enough to potentially burn valves in the engine, causing very expensive damage to the engine.

The slight click you often hear when depressing the brake pedal is usually the brake light switch that is attached to the brake pedal, which can make a loud enough click to be heard.