Engine cuts out irregularly when hot - advice please

Hi

I have a 1989 1.8 k-jet golf gti cabriolet.  The car starts from cold ok and will occasionally break down when hot for no reason.  It then struggles to start but always eventually does.  I have checked the fuel system pressure which is 5 bar and the control pressure which is 4 bar when hot.  When driven with the pressure gauge test equipment connected the car broke down but still showed fuel pressure at 4 bar but did not fire until the engine was cranked a number of times.

Recently the car has had new fuel injectors, the fuel filter replaced and the gauze filter on the WUR cleaned.  The electrics have all been renewed - cap, leads, plugs.

Any advice please!

Hot pressure is too high, should be nearer 3.5bar, although I doubt that is your problem.

What is the state of the fuel filler neck ? Sounds like you could be trying to run on water, does it ever misfire under load ?

Another culprit can be the lift pump in the tank.
I have also seen a dodgy ignition switch cause this.

How does it stop when it does, clean kill or a splutter ?

Not sure on the fuel filler neck, will have to check this, why the filler neck do they perish and let water in?

The car stopped on 5 occasions yesterday on a 5 mile journey, I had gone about 20 miles prior to this with no problems!  The first time it cut out it misfired, after this it did not misfire but was a clean kill and it took ages to restart.

I am afraid that is the most common mk1 fault, they rot out because they are mild steel and poorly protected from the factory and all the road crud gets flicked up onto them.

You will have rusty particles and water in the tank which in the worst case rusts the inside of the metering head, water blocks the fine metering slits, but eventually falls away to allow fuel through again.

Anyway before we cast doom on it, have a good look and feel of your filler neck. It still could be electrical if the neck is sound.

Thank you, will have a look tomorrow and let you know.

Thank you for your help!