Hello. We bought my wife a 2001 NB GLS 2.0 a couple of weeks ago. Got a screemin deal on it but knew it needed some work. It had a rattling sound from the exhaust that was determined to be the cat. So we had it replaced. We put in a universal Magnaflow cat. To this point the check engine light had not been on at all. As soon as she left the shop the CE light came on. She went back into the shop and they said it has a cracked exhaust manifold and MAF sensor was the error. Is this typical of these cars?