Hi. I have a 98 Civic LX (manual trans) with 192 000 miles on it. It was getting at least 37 mpg until my check engine light came on (Code P0420) for the cat converter. At that point the gas mileage was around 34 mpg. I took it in to confirm the cat converter problem and they found that I have a crack in my exhaust manifold and they replaced the converter. Since I got the car back, my gas mileage is even WORSE! I don't understand how this could be. I'm lucky if I get 32 mpg. I had a major tune-up done less than a year ago and had the timing belt replaced. Any idea what the problem could be? Is it something the mechanic did? The car also idles a bit rough.
Monday, January 30th, 2006 AT 3:09 PM