Hi there,

I've been having an issue with my 2007 Volvo XC90 for a few weeks now and two mechanics can't quite pinpoint the problem so I'm hoping I can find some help here -it's driving me nuts!

A few weeks ago I was driving about 30 minutes or so on the highway and my engine light came on. Continued to drive it for about another hour and then back, didn't hear anything. Next day I drove it for a half hour and this high pitch whining noise started when I parked my car. It's really, really loud from the outside and coming from underneath the hood near the engine. It sounds exactly like this:
The noise isn't happening all the time, it happens usually when I drive for about 30 minutes or so after I get off the highway, however this morning the noise started earlier than usual. I took it to two mechanics but they're not 100% certain what it is because it hasn't made the noise for either of them (even after they try driving it). The first mechanic said the engine code is reading the catalytic converter. Could this be the issue?

One thing to note - when I accelerate, the noise stops but when speed decreases the noise will come back on. I tried it during city driving and on the highway and it does the same thing. Does anyone have *any* idea what's going on? The nearest Volvo dealership isn't close, but I'm starting to think I'm going to have to bite the bullet and take it there.

Thank you!

 

When the noise is happening, pull your oil dipstick. If it stops, you need a PCV breather box.

 

I'll try that hopefully tonight. Would the breather box issue be happening even with the noise stopping when accelerating and then coming back on after taking foot off the gas you think?

 

I'd be surprised if this wasn't a breather box issue.

 

So I went home and my car was making the noise so I pulled out the dipstick and...you guess it. The noise stopped. Thank you for your help! Question - I have an appointment with Volvo on Friday to take a look at my car. Should I let them know I believe this is the issue and see how much it would cost for the part/repair? Is it frowned upon or not allowed to buy the part on your own and have them install?

Thank you!

 

Depends on the problem and the advisor. Some might give you a hard time and say they want to diagnose it. Others might agree that's likely the problem and replace it.

If they give you trouble, just ask them to replace the part and tell them if it doesn't fix it, you understand its not their fault.

Labor shouldn't be more than one hour.

 

So I took it in this morning and I told them I thought it was a breather box issue. I had mentioned the 'catalytic converter' code when booking my appt online when my engine light had come on. The engine light is off now (it must have turned off the past couple days, I didn't notice when honestly). He said the catalytic converter could also be making this noise (do you have any knowledge of that?). I'm mad at myself for mentioning the catalytic converter bc I hope they just don't say "oh that needs to be replaced" bc I know it's pricey.

If they do come back and say that, do you suggest I still move forward with replacing the breather box first and see?

Thank you for your help, btw! (I'm a young female so I try not to get taken advantage of in situations like this).

 

They said it was the breather box but they're charging me $500 to do it - which I believe they're stiffing me on a bit from other forums I've read? I don't have the tools and this issue has been on-going for a month without diagnosis and between the amount of mechanics I've been to, ubers I've taken, etc. I just said screw it and am having them do it.

Thank you for your help.

 

Ask them the parts and labor breakdown.

They are overcharging because they think you don't know it. There is a standard time guide, so it is easy to call them on it. Then I'd raise hell and you might wind up with it for free.

 

I got the call that the car is complete so I'm going to pick it up in a few hours - should I address this when I go to pay? They charged me $150 to look at it but would "go towards the cost of the repair" and gave me a loaner car to use in the meantime. Grr, this makes me really mad. I even told him it was the breather box to begin with.

 

I would absolutely bring it up. The AllData time guide says it pays .6 hours, so really they shouldn't charge more than that.
But worst case they might charge 1 hour.
Multiply that by their labor rate (presumably $150 since that is what they wanted to charge to "look at it".
Then add the price of the part.
That is what you should pay.

There should be no diagnosis. This is why I said to just call and ask for a price to replace the part and then make the appointment for that.