i noticed yesterday that about every20-30 sec while idleing my car would miss out, or just bog for a second. Well today i pulled the spark plugs and they were kind of ashy looking im not sure if thats normal. Today it got a little worse about every 5-10 sec. yesterday when i noticed it doing this was about 30 min after i bought premium gas from a differant place than usuall. i filled up at the shell tonight with premium and it still does it not really as bad though. it doesnt do it when the AC is turned on, and i cant feel it while im driving. it sounds kind of like my exause is burping when it does this as weird as it sounds. ive heard it might be bad gas what do you guys think....any help is appriciated. thanks!!!

 

could be bad gas. try running a good name brand fuel system cleaner. if that dont work...even though it gets spark it might not be getting it constinatly. replace wires and plugs.