Evap systems are a pain in the neck. That charcoal canister connected to your fuel tank is at the top of the list. Before you shell out big bucks to have your charcoal canister replaced, see if you feel like doing it yourself. And here's another tip: Stop topping off your fuel tank. Topping off can cause an overflow of fuel to drain into your charcoal canister, ruining it.

EVAP leaks can be as small as a pin hole. A tool like SMoke Pro available from http://www.aatecusa.com is a great way to locate those tiny leaks. Leaks commonly found in automobiles are rotted, broken or disconnected vacuum lines, leaking gaskets and fittings, cracked or broken plastic components, leaking diaphragms and seats, worn throttle shafts, leaking or cracked exhaust or intake manifolds, catalytic converters, under dash climate control and central locking system leaks, brake boosters, charcoal canisters, wind noise around doors and windows, even leaky headlamp and tail lamp housings to name just a few.
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