that is for sale and I went to look at it and in the car was a Failed Emissions report. the NOx was almost double the state limit. I've read that the EGR can cause this(maybe carbon buildup), or engine overheating, high compression due to carbon buildup, or timing issues. The car has about 180,000 miles on it and is selling for under 3000. Is this still worth looking into? Does the dealer have to cover costs to pass emissions?