Q: Why is my car still misfiring and smoked when idling

asked by on December 07, 2016

Got a car topped off oil and added Lucas stop leak changed spark plugs car still idling ruff and misfiring when speeding up you can feel car shake and misfire it tried to keep up but it's like it's choking and when I stop at lights it leave a small to a little larger but when driving slow no smoke or at speed no smoke and the tail pipe while idling you can hear and feel the car misfire and all from tail pipe but it don't smell like my caddy and my caddy is has a bad head gasket

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