I have my car repaired at Carls three times now. He has been very professional and has went out of his way to accommodate my schedule and has kept the pricing very reasonable. I don't get any sense of him being "Shady" whatsoever. I don't know what happened to the other reviewer but the check engine light can come on for dozens of reasons.
The reason I first went to Carl is that he had gotten such good reviews on the Vegas City forum. I am bringing my car in again tomorrow and expect I will get another round of great service.