Porsche 996 exhaust blowing; Gasket? Hole?

[dom9]

Gents,

Went on holiday for a week and came home to find the car running beautifully as normal.

Drove down the Father-in-law's for a BBQ at the weekend, went to start the car the next day and the exhaust is VERY loud.

It sounds like it is coming from the passenger side bank of cylinders and sounds like a very aggressive sports exhaust.

However, once the car has warmed up, the noise goes away.

I stopped at the petrol station the other day (for no more than 10mins) and the car was hot, and it still did it for a few miles down the road when we left.

I am assuming it is a gasket or joint, hence when everything heats up the 'gap' closes... Anyone think it might be anything else?

Car is into Autofarm for some other work soon and I am having the manifolds and gaskets changed anyway... Just not sure i want to fork out for any other new parts!

[porscheuro]

where the cat joins the manifold the nuts are known to corrode away leaving just a bolts and some rust and sometimes opens up the gap .... if they are looking at it they may put you new nuts and gaskets on the joints anyway as they dont cost the earth..

[dom9]

porscheuro said:

where the cat joins the manifold the nuts are known to corrode away leaving just a bolts and some rust and sometimes opens up the gap .... if they are looking at it they may put you new nuts and gaskets on the joints anyway as they dont cost the earth..

Cheers for that... I already have the nuts and gaskets (I think) so we will see if that cures the problem. I would go the whole hog and do cats and rear boxes, but they seem so expensive compared to a lot of other cars!

[hartech]

The problem can also be the bolt heads holding the manifold to the cylinder head and if so you really need a drilling jig to make sure you don't drill off centre and end up with a horrible out of position stud.

Baz

[dom9]

hartech said:

The problem can also be the bolt heads holding the manifold to the cylinder head and if so you really need a drilling jig to make sure you don't drill off centre and end up with a horrible out of position stud.

Baz

I wondered about this, but I am sure that Autofarm will be up to the job and the new manifolds are there and ready to go so they ought to pick up any problems while they are having a look.

[E8W]

Exactly the same thing happened to my car on Saturday. What was the outcome with yours in the end please ?

[dom9]

Holy thread resurrection!!!

Mine was the bolts between the cat and the manifold had rusted away and the join had opened up.

If you get under the car, it is usually easy to spot.