Hey All,

I'm trying to diagnose a hard to locate problem. I've attached a YouTube video of the noise.

Here's the link:

https://youtu.be/PAmanmQ0YVY

At the beginning of the video, I've got my camera down near the rear (firewall) of the engine on the exhaust manifold side. I then walk around the car and into the cabin. As you can hear, I put the car in neutral, apply the hand brake, and then put it in drive, and then back out. The sound is apparent when there's a nominal load on the engine, whether it's in D or R. It's the deep throbbing sound. At the same time, there's a metallic chirping sound.

First, let me say that I've a) had my mech guy diagnose it (a 30+year Volvo only guy) and then, on his recommendation, took it to a Volvo dealer and paid them to give me a diagnosis.

My Volvo guy (Peter) initially thought it might be engine mounts. The Volvo dealer also diagnosed the sound as engine mount failure. So Peter replaced the engine mounts. He also replace the serpentine belt and the transmission mount.

The noise is still there.

Peter thinks it could be internal engine issue, specifically a thrust bearing washer. On the other hand, the car is an automatic. It has 251,XXX miles on the original engine. It is a beautifully kept, fully serviced car, with an ownership history that shows superb maintenance at every level.

I own a '98 V90- had a mystery noise as well. For a long time- just could not determine where the noise (tinkling, chiming noise) emanated. I spent some time and money on the issue- finally -- discovered it was the front sway bar links- they tap against the frame of the body when loose- the nuts on top and bottom need to tightened quite a lot- use a 15mm "thin wrench to hold the inner bearing nut behind the rubber oil seal-

Hi,

After watching the video, I guess the metallic chirping sounds could be something spinning fast like worn alternator bearings or it could be something loose like exhaust heatshields rubbing with one another. A really loose heatshield would just rattle but this is just before that stage. The deep throbbing sounds could be the exhaust pipes & mufflers vibrating too much from their old rubber hangers/suspension.

Amarin.

Hi Amarin,

I was just passing by, using the “all” tab!
I agree with your post about bearings.
But most importantly the serpentine belts on cars can be an issue!
They make noises like a thumping while going over pulleys, especially, where there is a splice in the belt and a idler or tensioner bearing is running on the dry side of lubrications.
A belt tensioner can setup a rhythm and you never see it do a wiggling movement but the sounds travel into the brackets and engine block.
Stethoscopes can help!

I would take the serpentine belt off, for a minute or so and run the engine to listen for a change with less soundings. Chirps can be considered squeaks that are actually slippages into and leaving a groups of groove sides.
Really, their just a bunch of V belts made shorter in heights. All V belts age and make squishy sounds eventually. Some a lot quicker than others!
It’s why I have like the industrial belts materials better and consequently learned the differences.

The automotive brand GatorBack belts, made by GoodYear, are an extension or play against these.
Now, Continental purchased into GoodYear design and its unique material composition. They are emerged into their Elite branding.
They didn’t buy the “GatorBack” or the “The Quiet Belt” trademarks, from what I can tell?
I hope the industrial belts are still made on the North East coast and that plant didn’t get closed!

If this car has lots of miles, it might be a timing chain or belt thumping and clacking. The engine has too many of “noises” in it, for me. One might be the metallic sounds of valve train noise or some piston slap. We don’t know the operating temperature. Newer thin oils don’t dampen sounds as much.

In the video, the darn key and seat belt chime kills the whole experience of listening!
Isn’t there a switch on these cars, to push in, or does it use the newer proximity gadgetry for sensing the door open.
He could have least closed the door with the window down!
Just goes to show you how we can adapt and ignore things!

Off I go, scrounging to find a post to entertain me!

Phil

Hi Phil,

You chime in at the right spot of time!

Now that you've mentioned it, I think it could be the tensioner bearing too. The OP had changed the serpentine belt by the way and noise still there!

Agree with you about the belt should be taken off for a while. Should spin the tensioner bearing to see any undue play. Temporarily run the engine without belt might help too!

Agree with you the chime does somehow mask the listening experience.

You said stethoscopes might help, and I say a can of WD40 does too! Just spray at where the noise seems to come from, not on rubber things, but on any spinning part ie the spindle/shaft. It will evaporate away later.

Meanwhile, do stay safe and Covid free!

Regards,
Amarin

Harborfreight mechanics stethoscope. It's the only way to locate the noises. Have you ever had the transmission screen filter changed.?

The chirping sound in your video sounds a lot like what I am experiencing with my 1992 245 with M47 at idle sometimes. But that's where the similarity ends, I don't have the rumble.

I can understand Peter's thoughts about the thrust bearing, because I can make the chirp go away by only slightly touching the clutch pedal.
I'm shooting in the dark here: torque converters have thrust bearings too, right?

Hey, thanks Greg for your reply.

I don't know about the thrust washer on an automatic. I thought they were found on manuals.

FWIW, I'm taking it back to the dealer. They charged me $175 to diagnose the problem, and they obviously didn't do that. I hope they have the capability to figure it out the second time around.

thanks again,
Makenna

You need more data. Can you reproduce the noise by giving it a little gas with the brakes on? If so then a piece of hose or stethoscope may locate the source.