Strange noise - revisited

[Richard Jay]

Just after buying my 1997 Brava I've had a strange mechanical noise from under the bonnet, very slowly getting worse. I've previously posted here but have not been able to track it down (never does it at the garage or their too deaf to hear it).

Anyway thanks to the hot spell this past week I have determined that when it's very warm it doesn't do it at all. Today is a lot cooler outside and sure enough the noise is back for the first time in a week.

Does this give any clues to anyone ?? The cambelt has been replaced.

The symptoms are:

1) It happens either when the car is moving or if I press the foot on the accelerator (when stationary)
2) It is coming from somewhere under the bonnet (!)
3) It does not get louder or change pitch according to the speed of the car but doesn't happen when idle

It may even be a vibration of something metallic, I really don't know. But it is DRIVING ME NUTS so all help is appreciated.

 

[Wimmy]

HEATSHIELD!

I thought it was some cover around my cambelt as it started happening to me shortly after my cambelt change. It was a tinny raspingf noise slightly after acceleration. It was the heatshield above the manifold vibrating.

There was an earlier post this week to do with engine noise.

 

[Richard Jay]

Re: Re: Strange noise - revisited

Thanks Wimmy - but my heatshield is at the back but the noise is coming from the front ...

 

[andy1881]

Re: Re: Re: Strange noise - revisited

Ok sorry if this sounds a bit of a simple idea but if it happens when in neutral can you get someone to sit in the drivers seat to listen while you put your head under the bonnet?

andy

 

[alfanige]

a/c

Do you get a sort of metallic schlumm tock tock tock etc then quiet, followed shortly by a repeat?

Its just that when you mentioned the heat thing it sort of questioned the a/c compressor. I had a look at a Brava yesterday with the exact same thing and it was a bit noisy but worked OK.

Nige

 

[Sy]

Re: a/c

There is also a heat shield under the bonnet! where the manifold attatches to the engine, in the center at the rear of the engine