To keep fuel systems clean, TOP TIER detergent gasoline is recommended. See Fuel (Gasoline).
If TOP TIER detergent gasoline is not available, one bottle of GM Fuel System Treatment Cleaner added to the fuel tank at every engine oil change, can help. GM Fuel System Treatment Cleaner is the only gasoline additive recommended by General Motors. It is available at your dealer.
California Fuel Requirements
(Gasoline)
Fuel for Diesel EnginesCamshaft Timing Drive Components Cleaning and Inspection Valvetrain Valvetrain Timing
Cleaning ProcedureClean all the following components with solvent:Crankshaft sprocketPrimary timing drive chainPrimary timing drive chain shoePrimary timing drive chain guidesPrimary timing drive chain tensionerSecondary timing drive chainsSecondary timing drive chain shoesSecondary timing drive cha ...