Q: I have a code reader and it show P0446 mod$10 1 of 1 evap emission control system

Hi. Diagnostic Trouble Codes do not identify the parts that are faulty. Codes merely set as a consequence of the Engine Computer receiving out of range data. If a wire is corroded in a multiplexed "system" with ten sensors the computer will receive "out of range" data for all ten even though not a single sensor is faulty and the entire problem is a loose wire. Codes are even set as a consequence of almost completely unrelated systems failing. What you need is a Diagnosis and that merely starts with the Code as a clue to where to look and what to look at. The Code P0446 could be set as a consequence of a broken wire or, in the worst case, be a consequence of a faulty PCM. The faulty wire will cost you nothing to fix if that is the problem and you find it. No matter how handy you are, the PCM will cost about $300 or more plus programming. No one can give you an estimate of the cost to repair unless a Diagnosis is performed preferably by somebody who is highly experienced. I encourage you to contact YourMechanic, get it diagnosed properly, and make sure that diagnosis is explained to you well enough that you are confident in the diagnosis. Regardless of who repairs it, do NOT replace any parts unless there is specific test data (preferably shown to you) that clearly condemns the part. Working on a car is just like working on a body...no parts are replaced unless you are sure! Hope this helps.