Engine noise only on a cold start

2006 Toyota Camry 105,000 miles During late summer I had serpentine belt and alternator changed, and in December, I had tensioner replaced because a mechanic diagnosed that will be the only possible reason, and denied it had anything to do with serpentine belt or alternator replacement so I forked out $300 to get tensioner replaced. Now about two week later the engine noise on cold start has returned. It is definitely on the side of engine where the drive belt is running. The noise lasts less than a minute and then it goes away, and on a warm start, it doesn’t make noise. The mechanic made the diagnose of tensioner replacement w/o even looking at the engine because it wasn’t making the noise when I got to his shop. What should I do? The mechanic offers 12,000 miles or 1 year (whichever is first). Could it be something other than the tensioner?

Describe engine noise.

Knock? Ping? Rattle?

Tester

Kind of hard to describe. It’s kind of combination of spinning and scraping noise.

What engine in the Camry?

Tester

2.4L 4-cyliner.

Have the work the last mechanic performed rechecked by a different mechanic.

Tester

I could, but that means more money. I’m hoping that it will be easy to talk to the mechanic to provide his warranty service he claims to offer. If he refuses to provide warranty service then I will have to go to another mechanic.

Then you have two choices.

Ask your mechanic to come spend the night at your house so that they can listen for the noise when the engine is first started?

Or, drop the vehicle off at the mechanic so it sits overnight so they’re able to hear the noise when the engine is first started?

I know which one I’d go with.

Tester

"Then you have two choices.

Ask your mechanic to come spend the night at your house so that they can listen for the noise when the engine is first started?

Or, drop the vehicle off at the mechanic so it sits overnight so they’re able to hear the noise when the engine is first started?

I know which one I’d go with."

LOL.

If the lash adjsuters of your engine is hydraulic, then that could be the issue.

The phrase “Customer complaint could not be replicated” comes to mind…

;-]

Need a little clarity here.

Did the noise start when you had the alternator and belt replaced or was it making the noise before this work was done?

If it started after the work was done, did it start immediately or sometime after?

The tensioner was replaced and the noise went away for two weeks, then returned. Is it the exact same noise?