myvw777

Hello, i've got an issue with a P0431 code that keeps coming on. I think a GURU might be needed on this one. I have had this code problem for quite a while and here's what is going on. When i first got the code i went to get an emmisions test done to rule out that the cat(s) were bad. the emmsions passed with flying colors. so i swaped the front O2 sensor to make sure the O2 sensor (bank 2) was bad. Sure enough the new code was stating the bank 1 when i swaped. so i replaced the O2 sensor, then it showed the same code again! so i figured maybe BOTH were bad, so i replaced the second front O2 sensor. everything was fine for about 4,000 miles until recently. I now have the same P0431 code again!. Basically i have no idea what else to check. I cleaned the MAF screen, checked out the vacuum lines for breaks, replaced the spark plugs with Bosch plantinum+4's and still no difference. I am still getting the P0431 code. Any ideas anyone? Thanks for any help. I have a VW passat, 2001, ATQ engine, V6-30valves. Manual transmission. and i have 37,000miles on the car.