I have a 97 gtp. It runs rough almost like a miss around 1000 rpm. But idle is fine so is past 1500. Service engine light is on not flashing on. So is abs and airbag just saying. The car sat for a year or more before I got it. So could it be bad gas. And I have a fuel line leakin some where near fuel filter toward tank. Also hid is non working. Help please.