Hello, I bought my car 1 month ago and there was no problem, but after 1 week, my car started to misfire and not use gas. It stalled twice and did not happen again in the same day. Today I brought it to the mechanic, he looked at the system etc. There is no problem. When the malfunction light comes on, it gives an exhaust emission error and they found the problem is changing. When they checked everything, it starts from 10 billion in the brains. What are your thoughts? Please help.