Check Engine Light going on - need some help

[WendyH]

Hi, thanks for your reply.

I just had the fuel filter changed, platinum plugs put in, etc. I don't have any fuel mods. I also just had a new exhaust pipes / cats done and had the O2 sensors changed. Here is a big issue though, when I bought the sensors from Advanced Auto they said the car needed 4 sensors - 2 upstream and 2 downstream. The H pipes only had place for 2 and the mechanics put in the downstream sensors. Not sure that I have the correct sensors installed and can't find what is correct.

I recently put in a KN air filter, but haven't done anything with the MAF.

I have owned this car for 4 years and have always put in 93 octane.

After having the complete tune-up, putting in the new air filter and having the exhaust system done, the car still didn't pass inspections (emissions).

Any ideas? My regular mechanic couldn't figure out what to do about the codes, so he recommended someone. I'll be bringing the car in next week, but would love to have some more information before I do that.