tonight i was driving home and my car starts to bog down so i try to keep the revs up so it wont do it but it did every gear i was in, the power kept bogging like it stunners in every gear plus its back firing randomly in whatever gear i was in. plus i had a misfit last winter but i replace all the spark plugs and got a new coil pack. i even replace the fuel filter can anyone tell me what this problem? thank you [scratch]