Yes, B-12 Chemtool Fuel Injector Cleaner (part #0116) is extremely effective in the removal of gum, sludge, and other deposits immediately before an oil change. To do so, pour into your cold crankcase approximately 1½-2 oz. of #0116 per quart of oil capacity. For instance, if your vehicle holds 5 quarts of oil, then you would use 7.5-10 oz. of or about half to two-thirds of one can. After you’ve added it to your cold oil, start the car and run it at idle 10-15 minutes until the oil is warmed up. Then change the spent oil and replace the oil filter. If the buildup is quite severe, it may require a few applications.