My name is James Edwards, Southbury, CT and I own a BMW 2006 X3. My car has 71,000 miles with an automatic transmission and auto stick shift. My question is: my car has a skip when accelerating and after shifting. I have replaced spark plugs, fuel pump, mass airflow sensor and the air filter. I have had all regular services done and the dealer is unable to determine the problem. Last dealer visit was six months ago and they attributed the problem to bad gas with a high level of ethanol. I have always used 93 octane consistently. Would you be able to help me with this problem? Thank you.