Exhaust smoke & crack in exhaust - 996 c2

[damonbill]

I'm hoping this is a non issue but it would be good to see if this has happened to anyone else:

My exhaust started blowing last week - it was blowing on start up but then after 5 mins of driving. It looks like some nuts on an exhaust join have rusted causing it to come apart, then as I drive it warms up and expands and seals up.

I started the car this morning, blowing as per usual, but it started with a cloud of blue smoke then settled into some whiteish smoke coming out. I didnt do a long run to see if it clears up.

I can see where the exhaust is blowing, its between the engine and cat, so would this mean slighly smokey exaust is not so much of an issue? The blue smoke did concern me a little as this is prob oil.

I have a big service coming up, so might just try not to drive till then.

Engine sounds normal - not lumpy idle or rattle etc.

 

[Uncle Monty]

It's normal to get some smoke on startup but if it persists beyond say 5 seconds it could be your air/oil separator needing replaced.
I don't think the exhaust crack/split would cause this , more likely a coincidence.

Let us know how you get on.

 

[damonbill]

Will do, cheers

 

[Shalmaneser]

If the crack in the exhaust is before the lambda sensors it will mean they are not able to meter the fuelling correctly. However, the car does not use them for the first~30s after the engine has been started as they're warming up. So symptoms do seem a bit odd.

Probably wise to avoid driving until the servie.