Vauxhall Vivaro engine cutting out

I've just done a fuel Oil And air filter change plus all fluids for a service egr valve and mass air flow sensor, but when I start the van it runs the just dies then I switch ignition bk to try to restart at takes a few seconds but fires bk up then it runs a dream it's not every time I start it but def nearly every time first thing in the morning. N it sure if I got air trapped in fuel line if so how do. Remove it all help gratefully received.