Thanks everyone for your suggestions.
Gazza82 I will try I will check your Questions out tomorrow and hopefully have results to post.
Rockhopper & ronb 65, no lights no ecu codes but engine mounts now that is interesting because it feels like something is making the engine do an instant stop/recover in a way it would rock due to torque I suppose hence the thud feeling.
Below is a previous post with list of stuff changed.....
After many nights reading other threads and trying other peoples ideas I have finally found (and cured) the problem. As far as I know no one else has mentioned it before. Fiat ECU scan kept telling me that lambda was cold/bottom limit and yes the plugs were sooty, so no lies there then.
I changed out the.......
Spark Plugs (NGK)
Thermostat housing (FK)
Temp Sender (Alfa)
Throttle Body (Alfa)
Idle Control Actuator (Bosch)
Lambda Sensor (Bosch)
Oil & filters (Mobil 1/Fram)
Timing & Balance Belts (Gates)
Water Pump (FK)
And many ECU & Actuator resets....Nothing, Nowt, Nada, Nichts. Only the Variator had any distinct effect on the actual sound of the engine i.e. no longer sounds like I would be asking passengers for a Fare.
So check all the hoses, inlet etc.... Still nothing.
I could hear (now that the Variator was quiet) a slight metalic crackling noise on the exhaust manifold No1 area, so squirted water on it....The venturi action sucked in the water and pruduced rain clouds from the back of the car. Thank **** for that, off with the manifold, clean up new gaskets and ....no.....still rain clouds when water applied. So off again with the intention to use exhaust goo to help seal the new gaskets. Before that I thought about the manifold/welding, so using turps or other fine oil, apllied it to the pipe work then looked inside and hey presto it leaks through on all cylinders. Now TIG welded on the outer plate area and reassembled it's PERFECT. Lambda reads as it should, plugs are normal tick over/idle spot on. How many other Alfa's out there are going to be the same ? and going through a lot of go juice and failing emmisions being sold lambda's and CAT's they don't need ?
Now my only prob is overheating, trying to start again after a 15 min run feels like the engine is stuck solid, let it cool and away ya go. any one got any ideas on that ??????