I have a 1999 2.8 V6 A4 Quattro. So a few weeks ago the CEL turns and I pulled the codeds. It read P0441. The car had an issue starting everytime I re-fueled. It would not start and I would get the P0441 code and a misfire code as well. After reading the forums, some suggested that it could be a bad Purge Valve casuing the engine to get flooded during fill ups. I replaced on thursday and on friday morning the CEL light turned off by itself. The previous valve didn't tick like the new one does. I re-fueled and everything went well. Come monday morning the CEL light turns on again showing the same P0441 and now a P0422. WTF could be wrong now. Any help would be great. Thanks

 

Code P0422 - Main Catalyst , Bank1 Below Threshold

Your catalytic converter is probably going old. On OBD II cars, 1996 and newer, two oxygen sensors are used in the exhaust system in series mounted ahead and after the catalytic converter. The first sensor provides data used to adjust the air/fuel ratio by the ECM while the second sensor’s data is compared to the first to ensure that the converter is effective in reducing the level of hydrocarbons. If the values are too similar, the ECM sets a code indicating the converter may not be working. This is your situation

Code P0441 - EVAP Emission Contr. Sys. Incorrect Purge Flow

This indicates that a part of the EVAP control system is no longer fuctioning correctly. The EVAP system consists of many parts, including (but not limited to) the gas cap, fuel lines, carbon canister, purge valve, and other hoses. The (EVAP) emission control system prevents the escape of fuel vapors from a vehicle's fuel system. Fuel vapors are routed by hoses to a charcoal canister for storage. Later, when the engine is running a purge control valve opens allowing intake vacuum to siphon the fuel vapors into the engine.

EVAP emission canister purge is contolled by a valve which allows engine vacuum to pull stored fuel vapors from fuel tank into the engine to be burned, rather than be vented to atmosphere. A vacuum switch is used to detect when flow exists. If the PCM commands purge and sees that the switch is closed (indicating no detected purge flow) P0441 is set.

A code P0441 could mean one or more of the following has happened:
* Bad vacuum switch
* Broken or damaged EVAP line or canister
* Open in PCM purge command circuit
* Open or short in Voltage feed circuit to Purge Solenoid
* Faulty purge solenoid
* Restriction in EVAP solenoid, line or canister
* Corrosion or resistance in purge connector
* Bad PCM

 

Thanks for the info. I can scratch off the purge canister since I jjust replaced it. could the mis-fires that I was getting at after re-fueling cause the cat to go bad.

 

Also I was looking at the cats online and i notice that me car has 2. so which one should I replace if I have to or this code means that it could be both.

 

My car has only one cat but the error says Bank 1 so maybe it's the first one.
I really don't know what to say about the link between the misfires and the bad cat.

 

Thanks I will look into it