On older, less well maintained and "looser" engines, it is recommended just before the oil change so any blow by contaminants in the crankcase are diminished.Rex wrote:I think the "oil change" reference is more to create a routine of using 1 can every 90 days/3,000 miles.
Great point! Thanks for the info.texasoil wrote:If you buy good fuel (major brand with advertised cleanup performance) , you do not need any injector cleaner. As a general feel good, one bottle of Techron once a year is enough to keep injectors, intake valves and combustion chamber sparkling.
The powerful solvents found in 'fast clean-up' formulations are very hard on the fuel pump, flexible hoses, injector bodies, valve stem seals, engine seals and timing chain guides.
It ain't nice to beat the sh$! out of the various polymers (plastics) used in the fuel system and engine. Use those chemicals ONLY when indicated.