2003 Volvo S60 non turbo Howling noise under acceleration

[volvofanatic]

After I start the car and I start driving once the car is warmed up and i accelerate quickly between 3,000 and 4,000 rpm there is a howling noise that starts and as the rpms get higher the howling gets louder if i let off the pedal it instantly goes away and if i put my foot back on it continues. I noticed that it seems to be louder on a hot day (80-90) as compared to a cooler day (70-80). The car has no engine upgrades.

Any help is greatly appreciated

[regent]

Welcome aboard!

I've always thought it's the horses under the hood that make those noises

How many miles do you have, and do you know when the PCV was done?
Have you looked at the serp belt, sometimes oil contamination can cause slip and noises like yours, but I would put my money on a clogged PCV.

[volvofanatic]

I wish that it was the horses to bad there is is only 168 of them

The mileage on the car is 127,000 and I have no clue if the pcv was done.
Today I looked at the serp belt and it looks clean. Is there a way to tell if it is the pcv other than just the noise?

[Sagan]

I wish that it was the horses to bad there is is only 168 of them

The mileage on the car is 127,000 and I have no clue if the pcv was done.
Today I looked at the serp belt and it looks clean. Is there a way to tell if it is the pcv other than just the noise?

You can try the glove test. It worked for me.

[vtl]

B5244S's are not known for extreme PCV clogging. Did it this summer on wife's 2002 V70 w/ 133k miles, it was ok. Oil trap was mostly sludge-free.

I would check bearings: serpentine belt tensioner, alternator, right front CV axle carrier bearing. First two can be checked with belt removed. To check axle bearing you need to ramp up the car, remove carrier bracket, pull axle down a bit and rotate bearing with your fingers. If it feels dry, or covered in engine oil - needs to be replaced.

[xHeart]

A very close match by regent and vtl.

It ran another 10,000+ miles with following two noises.
- Wheel bearing noise sounds like a red baron flying over at a distance on a Fway.
- Serpentine belt and tensioner's howling is visible at the shaking tensioner while it idles - separate from the engine noise.

After wheel bearing replacement which made the red baron go away, the howling became clearer.
An installed belt would not show a visible deterioration, remove it to examine. I replaced tensioner and the belt.

I have also replaced ALL mounts and pad -- 2 engine, 1 transmission, 2 subframe in past 2 years.
Driving is becoming therapeutic again.

[regent]

B5244S's are not known for extreme PCV clogging...Oil trap was mostly sludge-free.

The PCV clogging habits and service intervals may greatly depend on the driving duty cycle, climate (air humidity) and on the type of oil used.

[vtl]

The PCV clogging habits and service intervals may greatly depend on the driving duty cycle, climate (air humidity) and on the type of oil used.

Mine was a rental car, then it had 2 private owners. Last one was a lady, who poured olive oil in it at best. Then, 9 years after the car was manufactured, I bought it, being a newbie ("cheap Volvo, what a great deal!"). VVT solenoid was clicking, I cleaned it, and saw how dirty oil passage was. In next several frequent oil changes plus Seafoam something more tar-like than oil was escaping from oil sump. Then VVT clutch died (because of dislodged dirt). However, oil trap and hoses were mostly clean.

In contrast, oil trap on a newer XC70 was full of carbon buildup (dealer serviced, "proper" intervals, "Volvo recommends Castrol", blah-blah).

[regent]

..."Volvo recommends Castrol", blah-blah).

Sorry for the confusion with type of oil, I was trying to imply 'dyno vs synth' rather than brand names...