HOW DO I CLEAN OUT THE GAS TANK BREATHER OF A '99 FORD CROWN VICTORIA POLICE INTERCEPTOR
First please kill the ALL CAPS, they are difficult to read.
Why do you think it needs “cleaning?” I suspect you need to replace the charcoal canister but there could be other problems depending on the problem.
As Joseph mentioned, the only ‘breather’ for the gas tank on this car is the charcoal canister. There is no cleaning to it. If it is bad, you replace it. What symptoms are you experiencing? The evap system on this car should keep the tank under vacuum. A leak in any seals or vacuum lines would turn on the CEL for evap failure. The most common is a loose gas cap. Write back and let us know what’s happening.