Carbon build up problem

[MMBRAZIL]

Hello, everyone.
I have a 95 USA 993, but have no emission control in Brazil.
My question is, can I avoid the carbon build up, since I donīt need to worry emissions issues?

[Porscheologist]

The cause of carbon build up is worn valve guides that allow some oil to get by and if you do a lot of city driving in hot weather you will get carbon buildup around the auxiliary air-injection nozzles. These nozzles are in the secondary injection ports which are part of emmisions. Most European cars do not have these. Not sure about Brazil but if you have no emmisons I doubt you have secondary injection ports!

You will of course still wear out your valve guides eventually. But hopefully not for a long time.

[MMBRAZIL]

My car was imported from the USA so I guess it has the secondary injection ports.
Since I donīt have to worry about emissions, can I take out these ports or disable them from my car?

[AFJuvat]

The build up will trigger a secondary air injection fault in the system and turn on your "check engine" light.

Since you have no emissions, you can disregard the problem. As previously stated, it could be an indicator of worn valve guides, so you should have that checked.

The air injection ports are part of the heads themselves, and cannot be removed.

AFJuvat

[Porscheologist]

If its a 95 then he has obd1 this will not trigger a CEL for carbon buildup. Only 96-98 with obd2 will do this. So don't worry enjoy your car!

[MMBRAZIL]

ok, tks....