Please see attachment for belt noise on startup. I changed the serpentine belt and it didnt go away. Then I changed serpentine belt plus pulley/tensioner (Gates kit 90K38332) and did not go away. This noise only happens on cold weather starts (less than 50 degrees outside) and it goes away after car is warmed up. Any thoughts on which belt/pulley it could be? Thanks!

 

it could be your power steering pump or alternator causing the noise when it is cold. If it's the PS pump, gates has a $20 kit to rebuild the seals and NTN makes the bearing for around $13 dollars! If it's the alternator, denso is the OEM Supplier and is way cheaper than dealer.

 

With these types of noises always start with removing the serpentine belt and starting the car to confirm if it's any of the accessories on the belt.

If you can still hear the sound with the belt removed, obviously it's none of them (compressor, alternator, tensioner, PS pump).

If you can't hear the sound anymore after the belt is removed, continue investigation from there.

Since you already replaced the belt and the tensioner, they are out of the equasion.

So it's either PS pump, alternator or compressor (going from the cheapest and finishing up with the most expensive).

I would really hope it's the PS pump as it's the cheapest one even if you replace the whole assembly, let alone if you are simply swapping the bearing there.

 

is this something that needs to be done now? or can it wait until I hit the 105k mile service and have to change the timing belt? Im currently at 96k miles, its a 2011mdx.

Looking at carfax, at 52k, the power steering pump was replaced...not sure if that is relevant here?

thanks!

 

It's up to you. I would not be able to live with this sound or any similar annoying sound for that matter. But that's just me.

 

Until you diagnose the sounds you won't know for certain if it can wait or not. If it's the timing belt tensioner then you are pretty much ready for the timing belt service. If it's your alternator it could leave you stranded on the side of the road. If it's the power steering pump it could wait for a long time if you don't mind turning the steering wheel harder!

With the PS pump replaced at 52K, I'm leaning towards alternator but you won't know until you investigate

 

what do you guys think about starting off by changing the AC compressor mounting bolts?

 

It's relatively simple to do it from the bottom. However be very careful not to snap the old bolts - I replaced three and then snapped one five years ago. Had to leave it in there as I cannot imagine how it can be extracted without removing the bumper and possibly the radiator.