I was looking for suggestions to help with fuel economy; over the last 3 tanks my mileage took a dump, going from 8.6L/100km (about 27.3 MPG) Highway consistantly to 11.8L/100km (19.9 MPG). City mileage is absolutely horrible - 15L/100km (15.7 MPG). I could be driving a 3/4 ton truck for cheaper than that, but reading some of these posts, apparently thats pretty typical for some of you guys. Thats brutal. I've got about 180000 miles on the car so I'm gonna change the O2 sensor. Any tips on getting that sucker out? Lots of fire and brute force?