Hey, I bought my stock 00 GTP about a month ago and it was getting 24MPG on the highway and now I get 18. One day I was going about 80 going to work and my car started bogging down like it was about to die. Come to find out it threw some codes. A 305 ( 5 cylinder misfire) and a 103 (I think....it was something about the temp fo the car not reading correctly). I switched out the front plugs and wires (1 3 5) with some 606 autolite plugs and some NAPA wires. The service engine light finally went off a couple days later but it's still getting bad MPG.I took it to a shop and they said nothing seems to be wrong electrically.
The car had bad wheel bearings that were suppose to be replace before for I bought it. Is it possible that they weren't replace correctly and that's causing the bad milage? Any input would be appriciated.
