Cat heat shields on 997.2 C4S

[trendy old 997.2 driver]

Cat heat shields are fine but the mild steel securing brackets have completely corroded and the shields now sit on the cat and rattle freely! Not major, but very annoying. I know I should replace the whole lot but they are expensive for something I know will fail again and it seems OTT. Is it possible to simply get new brackets or has anyone done a DIY job on these? I like to keep my Porsche in A1 condition and don't mind spending on important parts (e.g. rear light clusters) but engine heat covers don't seem worth it or am I just being tight? I have plenty of time on my hands.

 

[b8575]

Other's may correct me but they are probably there for a reason. How important that reason is, is up for debate.

Anecdotally, many take them off when they fail and just don't replace them.

Mine were shot and removed and the car was fine without them for two years. I have only replaced them recently when I had some other work done in the same area

 

[spinnaker]

My only frame of reference here comes from lesser vehicles of the same sort of age. Probably best to keep them in place if you can. If the nut/thread hasn't corroded away you can usually just put a big washer on and then bolt back in place again to hold it in position. Some people just pull them off and don't replace them.

 

[deMort]

The gen 2 ones are different .. you have the normal coil heat shields and a seperate heat shield over the cat .. this is normally the one that rots away.

Unfortunately this shield has the lambda sensor going through it which will need removing to replace with possible thread damage happening when removing these sensors.

The inner fixings for this can also be corroded and tricky to remove .. for the above reasons people will often just cut off the shield and leave it like that .

I'm not in either camp here , remove or replace and i'm happy with either method.

 

[P9XX]

My car is an early Gen 2 which has had both left and right catalyst heat shields removed for over 6 years, all of my ownership and presumably longer than that. I've had no problems with their omission in the last 6 years.

As deMort mentions, the lambda sensor needs to be removed to replace the heat shield. These sensors can get corroded in the threads in the catalytic converter and be very difficult to remove without damage to the sensor or even the catalytic converter. A wrecked catalyst would entail a new exhaust manifold/catalytic converter assembly with all the possible problems associated with removal of the corroded manifold bolts. Not to mention the possible expense.

I've chosen to not replace my heat shields.

 

[trendy old 997.2 driver]

Thanks everyone. Your opinions are valued and there seems to be a growing consensus here! I'll probably wait until the spring and strip it all down and have a good look before making a decision though my recent service has given me a bigger concern about the corroded sports exhaust bracket that may mean a new muffler!