California smog woes

I've got a 96 Tacoma an there's a smog valve on driver side under hood that always buzzes when engine is off mine doesn't make that noise any more does anyone know if there's a relay or a trouble tree to check this system out.

 

Download the pdf repair manual and look through the emission chapter. It sounds like you are talking about the evaporative emission system. The charcoal canister accumulates gas vapors from the gas tank, then releases them into the engine when the engine is running.

Is your check engine light (CEL) on? Did you already fail the smog test?

 

No lites I just noticed it wasn't cycling like it did the last 20 years I thought it might have a relay probably the selinod I'll check to see its got power, it's always passed emission tests