 help my car keeps jumping
ok i have a 2000 ford contour and i already had a tune up this year and i put bars leak in where the anti-freeze goes ok so that turned it brown and thats normal. ok i brought fuel injection cleaner to see if that would help with my car jumping and it does it while im driving down the road. ok i took it to a guy at my local auto zone and he said it was showing a miss fire on his computer. ok what should i do then cuz i have new plugs and stuff and i dont know why its jumping and yes my engine stays on but the man there at auto zone got it to go off. so please help me to solve this matter. thanks | 
