I would like to share my experiences on this subject. One must have an understanding in how to use the fuel injector cleaner. I have used fuel injector cleaner in my DeLorean and other cars every 1,000 miles with no problems. One thing to keep in mind is NOT to let the fuel cleaner to sit over a day's time in the fuel tank and the system. One should plan to use the mixed solution right away, such as in a long trip that is nonstop. This way, all of the mixed solution will be consumed in the tank. This process will allow the cleaner in the fuel to work its work moderately and not to over clean by removing the varnish, sludge and other fuel waste by product in concentrated amounts as it will do when it just sits in the tank for a period of time over a day. I have traveled close to 90,000 miles using cleaner every 1,000 miles since my ownership of my DeLorean with no problems with fuel injector cleaner. I do feel a difference after using it -- The engine does run better. Kayo Ong #5508 Lic 9D NY [Non-text portions of this message have been removed]