Manifold advice please.

[G5FTH]

Hi,
I have a noise like a blowing exhaust coming from my drivers side manifold. I replaced the gaskets and its the same. I bought "new old stock" manifolds from ebay but when they have arrived I notice they dont have a lambda sensor or a hole for one.
Other than this they are identical and obviously original.

Is it a case of cutting a hole in the manifold to braze/weld in a bolt for the lambda sensor or does anyone have any other ideas.
I could return the manifolds but they were a good price and I cannot afford to go down the stainless route.

Thanks guys.

[spend]

The standard narrowband sensor needs to be in the middle of the manifold so a very deep sunken 'bung' is used... You might well end up with sensor problems if you just welded a nut into the new ones.

Cutting the 'bungs' out of the old ones and having those welded into the new ones would undoubtedly work the same.

[QBee]

Have you tried listening to the manifolds with a listening tube, to work out where the leak is?
The most common source of leaks other than gaskets is where the 4 pipes go into one.
The fix is to get a welder to cut the pipe open in the precat area, marking the orientation carefully before cutting, weld up the weak point from inside, and reseal. You can remove precats at the same time. Mine cost £100 for the pair to be welded. Both were leaking.

[G5FTH]

QBee said:

You can remove precats at the same time. Mine cost £100 for the pair to be welded. Both were leaking.

Thanks, if I remove the precats will it not fail an MOT?

[Sardonicus]

G5FTH said:

Thanks, if I remove the precats will it not fail an MOT?

No providing you leave in the main-cat if you have already purchased those Ebay manifolds personally I would do what Spend says I very much doubt the chanc of buying NOS manifolds will ever arise again the bung issue is no biggie