v6 and 7 eighths!

Fuel pressure regulator.

Check the charging voltage - ECUs often do bizzarre things if the alternator output isn't correct.

Injectors?? Put it on an old fashioned crypton analyser and do a "Power Balance" test, that'll trace it to whatever cylinder(s) are the cause. Badger.

The one thing I forgot is that pre camshaft change it seemed ok, but its only since the airflow meter went tonto overfuelling that all has been bad in the garden of v8

Si

does the fuel pump run for a few seconds after being left overnight? if yes check leaking fuel pressure regulator ( petrol in vacuum pipe to manifold) or leaking injectors.

Had similar problem, chased it all around the engine bay , temp probes ign.amp etc, problem was solved during recent call back to landrovers to have the fuel tank changed, when they managed to flood the engine.

In my case 3 injectors were leaking badly, dumping all of the pressurised fuel into the inlet manifolds in about 10 minutes.

I'd start with a compression check, wet and dry.

John

Somebody said to me the first thing to do when a V8 3.9 EFi is not running well is to change the temp sensors for the ECU. When my V8 was running rough (over fuelling) I changed the ECU temp sensor for about 8 quid and now it runs perfectly. I measured the resistance of the old one at various engine temperatures before taking it out and it just gave random readings. It was not even close to the published specs.

I was kind of hoping this one would be suggested as that was my next course of action.

Si