hey guys my car is acting up out of no where it has an a/f gauge and it started reading that im running rich and i made the mistake and put 87 fuel in it i filled it up with 93 now but its still running rich it also smells like a old muscle car 9(best way to describe it) and now it sounds like my exhaust is rattling and the car idles high well i think its high at 1100 or 1200 rpms and when i turn the car off it like ticks and makes the sound when metal cools and pops ??? any ideas