Strange sound from engine

[Astr4twin]

I have a Lexus is220d with 25k on the clock. The car starts and drives great.

This last week it has just started making a strange sound when idling. It only starts to do this once the car has warmed up. Drove it all the way up to the dealership and it literally just stopped doing it the second the guy walked around the corner.

Not 100% on this but sometimes if i give it a quick rev it will cure it for a few seconds.

I posted a quick video on youtube to give you an idea of what it sounds like. In the video i have increased the revs to show you whats happening in greater effect. The car also rocks slightly side to side when i rev it.

Any advice would be really appreciated on this as i have searched everywhere to find something even similar to what i am experiencing.

http://www.youtube.com/watch?v=C1DM0Omde88&context=C39571e7ADOEgsToPDskIAzFMXTJBmxJFDieJAGLJ1


Thank you.

 

[Peter.N.]

The only unusual noise I can hear is a sort of in and out of phase sound, I would suspect its due to a drive belt or tensioner.

Peter

 

[wotan]

does it have a dual mass flywheel, or vibration damper?

Wotan

 

[wotan]

The only unusual noise I can hear is a sort of in and out of phase sound, I would suspect its due to a drive belt or tensioner.

Peter

That could well be the answer, I changed an idler and fitted new ancillary belt to my BMW what a difference.

Wotan

 

[Astr4twin]

Sorry for the delay in replying. I ended up having an early night.

To be honest i can turn my hands to most thing's, but can only really find my way around the very basics of an engine bay so please excuse my ignorance.

It is the in and out phase of sound i was worried about. If it was the drive belt or tensioner would that be something that would come and go?, would it be reasonable for it only to come after the car has warmed up? as it never does it from cold.

I was mainly asking to put my mind at rest as just to get them to even look at it, is £150 at the Lexus dealers, not only that but it's a good drive away from my home.

Was doing a bit of digging about and it seen this,

The chain tensioner is controlled by oil pressure -so its 'automatic' or self adjusting. the chain tensioner presses onto the chain slipper and there is no service intervals for these.

If this is something i can do myself or drop off in a regular garage and get sorted without getting ripped off that would be great.

Thank's again for your insight. Appreciated.

 

[Peter.N.]

A crude way to check if its a belt is to squirt some water onto it when the noise is there and see if it goes/changes.

Peter

 

[Mursal]

Might be worth slipping in to your local garage and ask them "whats causing the noise". They might even tell you for free.

Small independent garages may not have waiting rooms with deep carpets, but most offer a good service.

 

[Astr4twin]

I bought some Millers Diesel Power Sport 4 yesterday and threw some of that in the tank as my original thought was it was something to do with the injectors. Took it for a spin on the motorway for a good 20 minutes at high revs to clear the EGR out.

Was still making the noise when i got back home so figured nothing had helped.

Last night i disconnected the battery and left it overnight to reset the ECU.

Just been out for a good drive in it and MPG has gone up loads better than i have ever acheived in the year i have owned the car and the main problem with the sound/vibrating the engine was making has dissapeared completely (touch wood).

Hopefully it will stay away or at least get me through to when i get it serviced the end of next month.

Many thank's for everyone's help and advice.