2003 Olds Silh with 3.4L V6, 38k miles. Runs ok, but has fairly loud clicking noise on a cold start. Runs quiet after warmup. Anyone have any ideas?..Thanks
Howdy, first check all the fluid levels . Then consider adding 2 ounces of Seafoam to the oil and drive 20 minutes then change oil an filter. The seafoam is a great cleaner for $7.00 a can. How often are you changing the oil and filter ? Using synthetic oil? an using 5/30?
Your noise when cold and then disappearing after warmup sounds like a classic oil leakdown case; oil leaks down from the tappets when the engine does not run, causing valve noise on startup. If it disappears shortly after startup I suspect worn tappets, which is unusual in a vehicle this new unless the oil has not been changed very often.
Check in your earview mirror if there is also a puff of blue-grey smoke during the first moments after startup; this will indecate a leak-down situation.
Sounds like a stuck lifter. A product called “Rislone” has been freeing them up for many years…If you get it to free up, start changing your oil more often.