i dont know what was ur previous problem sir, but bardahl oil treatment, either 1 or 2, doesnt cure black smoke but rather white's ie caused by blow by and oil leaks. they thickens the oil and seal better, but dis only applies to low grade oil imo. use a good lube (either synthetics or mineral based), especially those made outta ester, and they have better seal protection, less oil loss through methods mentioned above. ive been using both types of bardahl oil treatment, and to be honest, if ur engine is very in good condition, u wont feel any different in terms of fuel consumption, performance, or smoothness. how was the condition of ur engine prior of pouring the treatment in sir? its good to hear u r experiencing good result with it, iam using bardahl lube now, better result compared to the oil treatment. like i said, nuthing beats good oil