Ford Focus (1998 - 2004) - 05 1.8 Rattle from exhaust at idle speed

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Mon 21 Jul 2008 13:19
05 1.8 Rattle from exhaust at idle speed - Norman77
This car is the older shape Focus.
Mileage is 59K
The exhaust rattles at tickover and is getting worse. The idle speed is 750rpm with a tiny bit of fluctuation.
Recently it has had a genuine Ford(Fomoco) coil pack and leads.
The complete exhaust is genuine and all hangers are there.
I think the noise is coming from the exhaust manifold pipe with the flexible wire mesh join/bulb thingy
Are these a weak spot?
I have moved any heat shielding along the exhaust length out of harms way (that i can see)
Any ideas folks?
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Mon 21 Jul 2008 14:47
05 1.8 Rattle from exhaust at idle speed - Screwloose

Rattles from the front of an exhaust could be a broken-up cat. When it's cool; bump the pipe with your hand and see if it sounds like lumps of broken ceramic in the foremost box.
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Mon 21 Jul 2008 15:04
05 1.8 Rattle from exhaust at idle speed - Norman77
I have done as instructed and there does not appear to be any noise coming from the exhaust tapped or shaken.

The catalyst is directly in front of the engine and is securely mounted in place. I have tapped this gently and no rattling occured.

It had an MOT at the end of March and passed with flying colours.
It sounds like something could be rubbing against the exhaust.

Its only a noise but its just irritating.
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Tue 5 Aug 2008 02:54
05 1.8 Rattle from exhaust at idle speed - FocusBoy
I had this problem on a 2.0. Replacing the centre exhaust box solved it for me. I too thought it was a heat shield around the exhaust but then realised it was the exhaust box. Other than being a nuisance, I would not have though it will have any effect on the car. The mot just checks for exhaust leaks and emissions so there would be no reason to fail it for having a slight rattle.
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Wed 6 Aug 2008 16:43
05 1.8 Rattle from exhaust at idle speed - BenG
Check the heat shields attached to the underside of the car are not loose or able to vibrate - try tapping them with a rubber hammer. Another possibility is corroded/loose internal baffles in a silencer, if the noise appears to be coming from a silencer and not the cat. Again, a rubber hammer is a useful diagnostic tool to get things rattling (when the exhaust is cold!).
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