hmm, i have a strange problem with my 88 3.0 V6. i posted about a week ago about a funny sulphur-ish smell in my exhaust that happens when i accelerate hard. well, i watch my rough gas mileage, and it recently went to total crap. i normally get 17-20, but now i get about 13 mpg. i didn't change anything at all.<P>i'm wondering if my O2 sensor could be out, and the ECU defaulted to a rich mix (avoiding a valve-burning lean mix)<P>well, i know the O2 sensor hasn't been changed in 40k miles, so i plan to change it. (anyone suggest who has the best price? ) or does anyone have any other suggestions?<P>thanks a lot. gene.