UK Car Repair: engine failure Vauxhall Meriva 2003, egr valve replacement, vauxhall meriva

Question
2003 Design Meriva 1.6v. Low mileage - 17,000. Inconsistent engine failure at speeds of 30-40mph, which can be precipitated by juddering. Previous EGR valve replacement 2005. High oil usage. Engine starts immediately after stalling, driving fine. Occurs only on long journeys (20 mins plus), usually after motorway driving. Normally only drive short distances, no motorway. Previously vauxhall garage unable to detect fault as not registering on engine management system. Any ideas?

Answer
This is a tough one but lets start simple, when was the fuel filter last changed?  They can get partially blocked causing the pump to heat up after a longer drive, they cool down fast because they are immersed in cool fuel. How heavy is the oil consumption?