Does this 2002 Porsche Boxster Diagnosis Make Sense?
 

Hey guys, just wanted to check with this community on a recent diagnosis my mechanic gave me on my 02 986.

I'm not sure if I trust my mechanic at this point. I've had so many repairs it's just unreasonable. And now they are telling me I need to replace another major part...

So symptoms:

My car started "squeaking" repeatedly a week or two after it was serviced by said mechanic. The serpentine belt was replaced. I'm thinking this could be a bad belt install or something... basically whenever the car is on, it repeatedly makes a high pitched "squeak" at regular intervals. This is intermittent... sometimes it doesn't squeak at all, and at other times it squeaks VERY loudly to the point where I can hear it on the highway in the cabin.

Most of the stuff I've read on this talks about the belt and not the actual pulley/alternator.

The mechanic is telling me I have to get the alternator and pulley replaced for $900. They told me parts were $550 and labor was $350. I found said parts for $150 on eBay, so at least it will total $500 when I provide parts.

Could a bad/failing alternator even cause this symptom (squeaking?) Does this make any sense or are they taking advantage of my ignorance?

They made it sound like my car could break down in the middle of the road, though this minor squeaking issue started over a month ago. It hasn't had any actual effect on the vehicle's performance, so far as I can tell.

Also as a side note, my brakes squeak like mad. I just replaced them and they're good, but they sometimes squeak really badly, especially when I brake in reverse. How can I fix this? The mechanic tried spraying lubricant in there and it was good until I went to a car wash a couple weeks later.

Thank you guys in advance, if any of you are in the DFW area, please PM me and we'll get in touch. I want to be more involved with other 986 owners

I use a non-squeal product applied to the back of the brake pads to eliminate squeal. This seems to work great and the only squeal that I get is definitely from the pad itself due to the compound and temperature when the weather is cool and the brakes don't have any heat in them.

It's probably over posted at this point BUT..... If it were me, I'd tighten every spark plug first and see what happens. The resultant noise sounds exactly like a pulley squeak or roller bearing squeak which are also cheap and easy to replace as a first attempt before laying out serious cash.

PS Most mechanics hate guys bringing their own parts and it does open the Pandora's box if the repair fails as it gives the guy leverage to blame it on the ebay part.

drive to about 30-40 mph brake hard a few times, (obviously on a quiet road with no traffic) and see how that works.

A Bad pulley could cause belt sqeaking. I had the problem many times, but with my A/C compressor pulley.