Focus Exhaust Heat Shield - GroovyChick{P}
The front part of the heat shield on my 99 Focus went rusty a while ago. It started to vibrate at certain revs. The two front most mountings were bent away by my local garage and the noise stopped.

Now, a few months later the noise has returned. I checked that the mountings were still bent away - and they are! It seems that the whole heat shield is now vibrating.

My question is - Does the car need the heat shield or can i take it off?
If i can take it off - how easy a job is it likely to be given that the mountings are rusty?

Any advice appreciated - PLEASE!

Focus Exhaust Heat Shield - Dizzy {P}

I'm not familiar with the Focus but I'm positive that Ford wouldn't fit the heatshield if it wasn't necessary.

Depending on where it is fitted, it may be there just for comfort (e.g. between the exhaust system and the floor of the car) or it may be safety critical (e.g. between the exhaust and part of the fuel system). Where is it fitted?

If you want to take it off (hopefully to replace or repair it), a dose of penetrating oil or diesel oil left overnight on the fixings should help them come undone.
Focus Exhaust Heat Shield - AlanGowdy
Never simply remove a heatshield - have it replaced if necessary. Ford wouldn't spend the money fitting it if it wasn't needed. A heat shield over the catalytic convertor is covering a component which reaches very high temperatures. Incidentally, don't park a car with a Cat on long dry grass - the heat could start a fire!
Focus Exhaust Heat Shield - ChrisV
As usual Dizzy (and Alan) is spot on with his advice. Just to give Dizzy some more info, there are at least two cat positions on the Focus, one is the "normal" one, two or three feet down the exhaust. The other is bolted directly to the manifold, i.e. down the front of the block behind the radiator. The second position particularly could cause problems with wiring and fans if the heat shield is removed.
Sometimes parts like this can be very cheap or unbelievably expensive from Ford. It's always worth checking.
The mounting bolts on mine also look badly rusted, I don't envy you the job of removing them!
Focus Exhaust Heat Shield - timp
This advice doesn't really help you, but...

I found after the first winter I had my Focus that many parts near the front of the engine were encrusted in road salt, including the heat shield. (The road salt seems to get in through the front grills).

In order to reduce the likelihood of rust, I cleaned as much as the salt off as I could, though it seems to adhere well to metal!

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