M50 warm running problem

[daimlerman]

My M50'd touring is being playful.

Runs perfectly when cold,but refuses to run at all above idle when at running temperature.

Any ideas,any-one?

[Brianmoooore]

As with any E30 coolant temperature related fault, the engine coolant temp. (blue) sensor, and its wiring, is the first thing to check.

[daimlerman]

Blue temp sensor checks out OK,
bloody thing is no refusing to commence when cold as well!

Fuller tale of woe;

I have had an erratic miss-fire for a while,engine randomly cuts out when on a light throttle.Like this morning,the thing would sometimes manifest it's self when stationary,slightly open the throttle to hold 2k rpm and it would cut out,drop to 1500rpm and pick up again.
More usually,it would be split second 'miss',either on a light throttle or when coming off throttle.Dipping the clutch would allow the thing to hold a steady,normal idle.
I have tried new plugs,replacement TPS,new fuel pump,s/h ECU,all of these give a perfectly running engine for anything up to three weeks,then the sodding miss-fire returns.
Last night,I was held up in traffic for a while,engine cut out and refused to re-start.I abandoned the thing and went out to it this AM,added 5 litres of petrol(the low fuel light was on),it started first attempt and drove normally for about a mile(until the temp gauge came upto the 'normal' position)then it spluttered to a halt and would only idle.

Towed home,had a fiddle and am now charging the battery!

[capri_rob]

Fuel filter ? If it's clogged or breaking up inside could cause all sorts of running issues ?