Car smoking car was running rough, replaced 2 ign. Coils, spark plugs, oii 10w40 & filter, removed & cleaned Both Cats(plugged). Car runs great but started Smoking. Smokes like a train, did not smoke before. Oil pooled on top of all 4 cylinders. Cleaned & ran for a few minutes still smokes pulled plugs to check cylinders & again can see oil on top of pistons.