www.jec.org.uk

I have just been advised that the rear exhaust manifold needs replacing, however there are 2 listed parts - one classified as air injection and bizarrely named except air injection. Is anybody able to advise how to tell the difference?

Tuffareo,

I'm not sure where you reside (if you update your profile with location etc, it's helpful for others to give more informed replies), so I'm not sure whether you have a UK or overseas car.

However, air injection is an engine / exhaust setup that is applicable in a lot of overseas territories where emissions limits are more stringent. In simple terms, air is introduced into the exhaust flow via a pipe into a threaded boss in the manifold.

It's not fitted on any 3,6 UK cars, as far as I know. You can fit an air injection manifold on a UK car, you just have to find a suitable bolt or similar to plug the air injection inlet.

Hope that helps.

Paul

To add, on UK cars at least, the manifolds from the XJ40 (xj6) are exactly the same, might make locating one easier.

If it has developed a crack it can be bronze welded but will need re-surfacing as well. Also if it is cracked, clean the in-tank petrol filter, main fuel filter and generally make sure the fuel supply and return components are not restricted as its usually a weak mixture that results in the manifolds cracking.

I would also bet that if one is cracked, they both will be!

ptjs & Pop Rivet,

Many thanks for your replies and have updated my profile and added a bit about me as Paul suggested. The car is a UK variant and original.

I have located replacement manifolds and will check all relevant sectioned mentioned by Pop Rivet to make sure the damage is not repeated.

Thanks again.