I have a 2001 Acura TL. I've owned it for 8 months with no problems at all, not leaking any oil or anything. its got 253,000 miles on it and ran great. then all of a sudden, on my way to work the other day,my traction control light turned on and my check engine light began flashing, and the car had an idle like a lawn mower. I had the codes pulled and it had misfires in cylinders 3,5 and 6. I replaced the spark plugs, which reduced the amount of terrible idling a lot, but now the exhaust pipe rumbles as if there is a restriction. I had the codes read again and it has the same misfires but it also has one more in cylinder 2. Not sure what the cause could be, and I don't want to spend money unless I know for sure. Any suggestions? Bad EGR valve maybe? or bad coil pack?