I have a 2000 gt 5 spd and i changed the spark plugs two or three months ago, but i got bosch big mistake. Battery needed to be replaced so i did, but now it cuts out as i acclerate in all gears went to autozone they said i had a misfire on cyl 6 and 8. then it turns out that it could also be the coils. does anyone know if this happens frequently?