Chevrolet Repair Questions? Ask a Mechanic for Answers ASAP
Some customers may comment on a ticking noise (similar, but not related to valve or lifter noise) that occurs 10-15 seconds after a cold engine start. The noise will last for 1 to 2 minutes, and will fade as the engine reaches operating temperature.
The noise may be caused by excessive piston to bore clearance during cold engine operation resulting from the specific piston design used in cylinders 1 through 4.
Service pistons for cylinders 1 through 4 will now be of the same design of those used for all production 2000 and 2001 for cylinders 5 and 6, and will have polymer coated piston skirts. Pistons in cylinders 5 and 6 are not exhibiting the described noise condition.