About every 6 months I have to have the fuel injectors in my Pontiac Montana cleaned at the dealership. I get a bad miss with a flashing check engine light. I get the injectors cleaned and it runs great. The dealer says that it is because of fuel quality and they do about 30 a week. Are GM injectors prone to this? My Ford doesn't have this problem and it runs the same fuel. Of course he didn't have an answer when I told him that. They only charge $40 or $50 to get them cleaned so it isn't terribly expensive. Anyone else experience this?