Strong induction noise

[tranmkp]

Wife's 99XC. 105k - no issues ever with the car other that all the issues the xc has. Told me she hears a noise when she is on the gas - I drive it easy - I dont hear a thing - I do a freeway ramp launch - Boy, do I hear it. Sounds like I dont have a air filter. When in park and she pressed the gas with me listening and watching - I hear nothing.

Aside from that car runs strong

[cattlecar]

Is the fresh air duct that goes from bottom of bottom of air cleaner hosuing to above left side of fan shroud in place?

[tranmkp]

Yes, it appears to be secure - tonight I will tear it all down to make sure - but as of now it looks intact - the sound is pretty strong - right behind the firewall...

but car runs fine.

[tranmkp]

Just occurred to me - while the car runs fine - I do notice that when parked, when I floor it, it bogs down or will only go to 4k - I thought it was a rev limiter but now Im not so sure. I have replaces the fuel pump - still on the original throttle module.

[JRL]

They will not rev above 3800 in park or neutral, there is a rev limiter

[tranmkp]

Good then - that's one variable I can check off.

[tranmkp]

tore into it tonight - looks like nothing that I can find is loose. Go figure - What I did notice is that the caps for the expansion tanks over times begin to shed their threads. I had wondered why my low coolant like would come on - turns out the thread were basically gone. That was a easy one -

Now back to the induction noise...

[tranmkp]

I notice now that if I shift to low and drive around the "induction" sound is not so loud - So I drove around in different gears, switching frequently. Now it appears (the induction sound) to be almost gone - I mean it was never that quiet to begin with. Is it the trans? Sure does not sound like a trans - shifts just fine and no noice - and that was only on hard pedal.

Any ideas?

[almostarctic]

Do you have the snow shield in place on the intake? When I removed mine the turbo spool was more easily heard. When I went to SNABB intake and an aftermarket panel filter, it's really loud. I like it. My wife doesn't gun it enough to notice.

[tranmkp]

It really did sound like an induction sound. but WTH, Im a RWD guy. A little bird told me it could be a motor mount and that the sound I was hearing was the motor body contact. Ok, what ever. It was so easy to diag motor mounts on 240's -
I put the car on the lift and used the pry bar on the mounts and sure as hell it was a collapsed right front mount. - Picked up a new one for 112.00 bucks at the dealer - its about the side of a cantaloupe! It took all of 5 mins to replace.

Crap - induction noise...

right. [nonono]

[JRL]

I think I've said this about 10 times now.
When you hear a louder noise/vibration or feel something out or sorts, 9 out of 10 it's the lower mount [sly]

For whatever reason, all they seem to be good for is about 80-100K miles, tops on an AWD Volvo but seem to stay together on a FWD car.
Also they seem to crap out much earlier on a 2.4T (gen 1) over a later 2.5T P2 wagon

[tranmkp]

JRL,

In my case it was only noise - there was no vibration, only noise. I will say that after replacing it does feel smoother.

[JRL]

JRL,

In my case it was only noise - there was no vibration, only noise. I will say that after replacing it does feel smoother.

So see there actually was a small vibration
I guess I know these cars so well, that ANYTHING out of the ordinary raises a red flag