Just an update to this. It's taken a while as I have been waiting for a custom pulley from the states. I changed the pulley and injectors, put the belt on and went to test it out then as it got fully up to temperature the steam came back but this time with the water in the footwells too. I bypassed the matrix so I can drive the car. How long can I run with it bypassed? Is there a more permanant solution which doesn't involve changing the matrix?