I purchased a used Hyundai. They promised to replace the spark-plugs, but after the purchase I was getting 16mpg. No check engine lights ever appeared. I went to service and they verified the replacement. I went for 2 more years unable to determine the loss of mileage. I finally decided to change the plugs through a private mechanic discovered that they had changed only the front three at the time of purchase - typical mechanic scam. I had already dealt with other deceptive sales crap but followed thru with the purchase. To find out that it wasn't just a sleazy sales manager, but a conspiracy with service is beyond reprehensible DON'T buy or get service from this scam shop!