Aug 22, 2010 · I have a 1997 E150 Van V6 (with 82000 miles) which is running very rough when put in gear and under light acceleration or cruising speeds. It seems to idle fine, maybe a slight bit of roughness. If you romp on it in acceleration, it seems to be smoothish... but might be light on power. As soon as you put it in gear, the engine shakes. Vehicle may idle rough and stall. Is My Ford MAF Sensor Just Dirty? MAF sensors have a tremendous tendency to get dirty and cause several headaches that may include: BAD gas mileage, higher emissions, and/or lack of power. For the most part, when one is dirty, the truck, or van or SUV seems to drive OK, but not with the same peppiness as before.