Fuel Evaporative control failure on 99 cabrio

Need to know the fault code first?

This is supposed to store fuel tank vapors in a charcoal canister when the engine is off, then feed them into the intake when running. Different ways it could fail: stuck open, stuck closed, etc.

The Codes are as follows po411, p1582, po304,po300

P0411 evap system fault which could be:

purge valve bad gas cap vacuum hoses on top of tank charcoal canister-which is where I have seen most of the fault. There is an electric shut off valve in the bottom which goes bad. But you got to buy the canister to get the valve.

P0300 & P0304 300 is misfire & 304 means cylinder number 4 P1582 Throttle housing- clean it first and see if fault doesn't come back.

I have to wonder who told you that you have an evaporative emissions problem.

P0411 indicates "Secondary Air Injection Incorrect Flow Detected". P044* and P045* indicate problems with your evaporative emissions controls

P0304 indicates a problem with your #4 cylinder misfiring P0300 indicates a random misfire

The P0300 and P0304 suggest it'd be a good idea to replace the spark plugs and distributor cap and rotor (if your car still has one).

P1582 seems to be more mysterious. It is a VW specific code that indicates your idle speed control is out of range. Is the car idling funny? Apparently a number of people have suggested different things including changing the oil, cleaning the throttle body, a faulty switch in the throttle body (closed throttle perhaps?), cleaning the MAF, or possibly an air leak in the intake

OK so far I have new airbox and charcoal canister and sparkplugs and cleaned the throtle body reset the computer and after driving 30 miles check engine light is back on. but now the only code I get is the p0411

so far everything I have done was needed ..the airbox was aftermarket K&N and the Charcoal canister was gas saturated (Very heavy gas oder) I'm sure the new plugs eleminated the other codes/problems. Where is the purge valve and is there something else I want to be looking for?

Thanks Mario