i recently got my car back running after sitting for 9months. it had a 1/2 tank of gas while it sat. when i got it back i filled it all the way up with new 93octane and a bottle of cleaner stuff. it is now down to 1/2 on that gas and is now running very very rough. it idles perfectly but when i put it in drive its sluggish and struggles to drive. its also fine when i put it in reverse. this has happened the past 2 days. it kinda does the same thing while im driving but its just a short hickup but the last 2 days it barely drives. any idea of what it could be?

 

Clogged fuel filter?