Hey guys,
So I had a rattle in my tensioner pulley. You could see the assembly moving when the rattle happens. So, I replaced the pulley. Didn’t help. So then I replaced the whole assembly. It rattles less, but there is still a rattle. Any ideas what else it could be?
Thanks!

 

When you replaced the whole assembly, that included the belt?

 

no, the belt looked fine (no cracks or signs of wear) so I didn’t think that would be part of the issue.

 

Remove the belt and start the car to see if noise gone, if so...........If not check the idler and other pulleys.

 

A while back, I had to replace the serpentine tensioner pulley because it was moving more than normal and making an unusual noise. At the time, I read somewhere that sometimes a vibration in the other serpentine pulleys (alternator, power steering pump) is transferred and amplified in the tensioner pulley. I'm not sure it's true, but I used a mechanics stethoscope to verify the noise was loudest around the tensioner pulley.

If your problem is still the tensioner pulley and this is your second assembly, the only thing that occurs to me that could be a problem is the bolts that attach the assembly to the engine. Maybe wrong torque or maybe previous owner damaged threads?

One last possibility is the belt. Mine looked brand new after 90,000 miles. I read they stretch with age. I imagine if they stretch too much, that could affect proper pulley tension (step 2 in the second page I attached 4-30).

I'm attaching pages from manual with torque specs in case you do not have them.

 

Serpentine belt doesn't stretch, the grooves wear.

 

Did you get rid of the noise? Any updates