S Type 3.0 2000 wth LPG - Possible Exhaust Manifold Leak

Guys,

Got a rough sounding S Type 3.0 v6, which also has LPG.

Sounds like a misfire/popping noise, with rattling from underneath near the engine and fumes coming into the cabin.

I have changed all spark plugs and coils (which was a pain as I had to remove the manifold) but this hasn't improved the problem. I had a similar problem with a Suzuki Swift, where the manifold was removed and the gasket cleaned.

Does this sound like a similar problem? In terms of codes, I got ignition coil circuit codes which have now gone.

I'm doing an advanced diagnostic session to it tonight with a Delphi scanner and will report back.

A video can be found here, any thoughts guys?


Thank you!