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Hi All

I've got a "noise" (not exactly sure how to describe it) that only occurs at certain speeds/revs - abit in 3rd gear and always at 2k in 4th.

As people have suggested, it is probably a heat shield problem.

I have tried to ignore it, but now can't stand the noise.

My question is, apart from the obvious shield over the headers, where exactly (if any) are the other ones?. The nose seems to come from the bottom front left, but really that could be resonating from anywhere.

Are they all accessible from the engine bay? Or will I have to get under the car as well?

Thanks in advance.

Most of the exhaust has shielding if it's standard, so jack the car up and wiggle and tap it at different places.

The usual culprit is a spot weld on the heat shield just where the exhaust exists the engine bay and dips under the chassis. The spot weld breaks allowing the heat shield to vibrate in a certain engine rev range.

There are a few ways to stop this noise.

Bend the heat shield away from the exhaust

Use a metal hose clamp to secure the heat shield

Install after market extraters....

J.

Front mount on my header heat shield broke & also one of the fork-like securing tabs on the 2nd front rear bullet muffler/ resonator broke. Difficult to see break as it all looked ok until you tested it by hand. From memory the heat shields for the cat & the rear muffler aren't a common problem.

Short heat shield on top of the exhaust just after the 3 bolt manifold connection, I got mine out of shape/position when I renewed the gasket it vibrated like a bitch at exactly 2900rpm sounded like $
I slackened of the retaining bolt and wriggled the shield bit thingo until it noved back a tad and was no longer touching the bolts or flange.

Thanks for the input guys.

So I had a look today. If I look into the engine bay from the gap behing the back of the left front wheel, there is this little plate just before the exhaust bends... I am guessing that the the shield that you guys are talking about?

I can reach it from the engine bay with my hand, but cannot physically see it. From what I can see, it is a little plate held on by 2 nuts. I am guessing this is the culprit, because when i grab it and give it a little tug and let it go, it vibrates and makes a ringing noise.

From the feel around, I don't think its actually touching anything and it is on pretty tight.

Can I remove this shield? It appears to be shielding some sort of pipe/hose below it. I tried to take pics but they are useless...

On a side note, taking out the jack I noticed a whiff of fuel in the boot. Is this normal?

goonie wrote:Thanks for the input guys.

So I had a look today. If I look into the engine bay from the gap behing the back of the left front wheel, there is this little plate just before the exhaust bends... I am guessing that the the shield that you guys are talking about?

I can reach it from the engine bay with my hand, but cannot physically see it. From what I can see, it is a little plate held on by 2 nuts. I am guessing this is the culprit, because when i grab it and give it a little tug and let it go, it vibrates and makes a ringing noise.

From the feel around, I don't think its actually touching anything and it is on pretty tight.

Can I remove this shield? It appears to be shielding some sort of pipe/hose below it. I tried to take pics but they are useless...
On a side note, taking out the jack I noticed a whiff of fuel in the boot. Is this normal?

Look down under the bonnet on the exhaust (passenger side) , you will see the O2 sensor in the exhaust manifold , directly underneath that is the manifold to exhaust flange , this has three bolts you will only be able to see one if you're looking straight down , right after that you will see a heat shield and after that an exhaust pipe clamp/retainer with a bolt that sticks out holding the exhaust pipe onto a bracket on the gearbox , this clamp holds the shield , not the manifold bolts
--this is the shield that made noise in mine .

If this is the one making noise you can remove it --I wouldn't-- my fix was , -slacken the bolt on the clamp and re-seat the heat shield so it is back from the flange and clear of the bolts tighten up the bolt again , mine gave me no more noise after I'd re-seated it.

Boot petrol stinko , mne did the same thing , take out the protective plate in the boot (10mm bolts) (the one that holds the jack handle) and tighten up the clamps that hold the main filler hose , check that the other hose and clamps are not leaking while you're there , leave the boot open when you park at night (if you can) it takes a while for the boot to get rid of the petrol nif , (A good hit ofGlen 20 helps) dont fuel up past the first click of the bowser when filling up.