Vibration/Noise at 2K RPM

[MattM]

Recently at around 2K RPM, whether accelerating or cruising, the engine note is a lot rougher and I can feel a vibration through the pedal. Any ideas? Thanks.

[v70torslanda]

Engine top mounting or lower strap mounting (rear engine tie bar) if I had to guess.

Plenty of incidences of both on here . . .

[MattM]

I recently replaced the engine top mount but the issue was occurring before that.

[v70torslanda]

Might be this, then.

http://i33.photobucket.com/albums/d55/shedbike/22711.jpg

J

[MattM]

How can I be check this to be the cause?

The bar that is connected to the top mount has a lot of movement in it if I push it, is that normal?

http://www.ultraracing.com.my/vgreenwap/image/model/Volvo/Volvo%20S60%20front.jpg

It's the one in this image, the bigger bar. Is it supposed to have a lot of play in it?

[richiemat]

yep the bigger bar is meant to be quite wobbly

[MattM]

Thought so. Is this one of those things I should just take it to a garage?

[thebadger]

It could be a duff exhaust mount... sometimes they cause an increase in vibes at a certain rev level.

Failing that if it is just after 2k revs it may be due to the turbo spooling which is a whole new & scary set of problems & costs.

My money is a dud mount on the engine or exhaust system, but I'd say exhaust over the engine mounts. Have you replaced the exhaust recently? Or the lower tie bar as J suggests?

[cornclose]

yep the bigger bar is meant to be quite wobbly

Unless it has washers around it.

The other bar though Matt is not standard, it's the Ultra Racing strut bar which makes a WORLD of difference to the feel and handling (just FYI...).

[MattM]

It could be a duff exhaust mount... sometimes they cause an increase in vibes at a certain rev level.

Failing that if it is just after 2k revs it may be due to the turbo spooling which is a whole new & scary set of problems & costs.

My money is a dud mount on the engine or exhaust system, but I'd say exhaust over the engine mounts. Have you replaced the exhaust recently? Or the lower tie bar as J suggests?

The exhaust does have a few issues. Both the hangers at the tail pipe and the center section have rusted off. I have however fixed the one hanger by the tail pipe but as yet have not done the center section, which is getting done when the part comes through.

I haven't looked at the lower tie bar, where can I find it? If it's anything like the top engine mount I replaced it could well be shot.

The car was in Volvo on Wednesday and it didn't show any codes, if that makes any difference regarding the turbo.

When the revs reach about 3k they are fine, it;s just around the 2k area where it is very noticable.


Unless it has washers around it.

The other bar though Matt is not standard, it's the Ultra Racing strut bar which makes a WORLD of difference to the feel and handling (just FYI...).

It looks very close to the bigger bar. Doesn't the bigger bar vibrate off the strut?

[cornclose]

There should be no vibrations as such from that bar as it is mounted using rubber bushes. That's why it feels wobbly.

[HammyUK]

Check you haven't got a split air pipe, mine was rough the other day and Volvo found a split charge air pipe causing it to run rough below 2/3k - also caused the plugs to foul slightly.

[MattM]

Check you haven't got a split air pipe, mine was rough the other day and Volvo found a split charge air pipe causing it to run rough below 2/3k - also caused the plugs to foul slightly.
how can i check ?

[HammyUK]

Volvo pressurise the system and then go round squeezing all the pipes to see if they hiss!
Otherwise just give them a REALLY good check over.

[thebadger]

The lower tie bar is roughly level with the right hand side of the number plate as you face the front of the car.

They retail at about £40 for a 3rd party, or you could buy that & the powerflex replacement bushes too.

If the top mount is done, it's a good place to look.

I'm sticking with my exhaust theory tho now that you've said there's missing mounts.

All that energy through one mount that's "sort" of fixed may be very bad.

[MattM]

The lower tie bar is roughly level with the right hand side of the number plate as you face the front of the car.

They retail at about £40 for a 3rd party, or you could buy that & the powerflex replacement bushes too.

If the top mount is done, it's a good place to look.

I'm sticking with my exhaust theory tho now that you've said there's missing mounts.

All that energy through one mount that's "sort" of fixed may be very bad.

I've got the other part through so I can fit it today

[MattM]

problem solved. turns out the exhaust was resting on a bar under the car. fitting the new bracket lifted it up and stopped the vibrations.

[thebadger]

Glad I picked the issue up for you. Did the exhaust get any damage from resting on the bar?