I have a 2008 Hyundai Santa Fe 3.3 V6 with 107,000 miles on it. The check engine light it is on and there are 3 codes. There are 2 P0441 codes (incorrect purge flow) and 1 P0133 code ( o2 sensor circuit slow response bank 1 sensor 1). I have taken it to my mechanic and at first he noticed the purge valve wasn't closing properly so he replaced the purge valve and the o2 sensor. The light came back on so even though he saw everything working fine after the first replacement, he replaced both of them again just to make sure. Codes came up again so he's not sure what to do because everything looks mechanically fine. Im being told to see someone with an digital oscilloscope (my mechanic doesn't have that) to look further into it. Does any one have any input? Should I take it to the dealer at this point or call around to find a shop with the oscilloscope? Any ideas maybe I can tackle myself before taking it else-ware? Thank you