I have just had an oil pressure problem sorted out, and today the engine management light has come on again?

code: 17544

Fuel Trim Bank 1 - system to lean

This points at many possible issues

Fuel pressure / pump

Injectors

Intake / exhaust leak

Air system

Hose leak

has anyone had this problem? as this code keeps returning after the light has been put out and we cannot see anything obviously wrong

Most liekly to be a split hose causing an air leak. CHeck all the hoses, particularly the one that runs infront of the engine, just to the right of the dipstick. You may have to remove the black metal plate through which, the dipstick passes to do this.

I'd agree with Goochie on that. Carefully manipulate the breather hoses with the engine running and listen out for a hiss as the air gets sucked in.

Will do in the morning - Cheers