well yesterday i changed the plugs put in some NGK's. The oil looks clean the guy i bought it from said he had changed it last month. I'm not sure what oil weight he used but i will change it soon to 5w-20, can i use 0w-20. also will a PCV trap help any with FE. and what about a fuel warmer. I'm also wanting to block the lower grill, what material should i use. I really like the look for a rear OEM style spoiler (wing) what will that do for FE.
I have exact same car what you have. My upper grill is fully blocked and lower is blocked 50%. Rear spoiler will increase aero drag, thus will lower FE. I would recommended switch to full synthetic Mobil 1 5W20. Fuel warmer doesn't work, I've tried that already.