Are you sure it's pressure and not vacuum ?
i.e. when you remove petrol cap is air rushing out or in?
(could be blocked breather pipe from tank - is petrol leak regular,or only when you release cap?)
Are you sure it's pressure and not vacuum ?
i.e. when you remove petrol cap is air rushing out or in?
(could be blocked breather pipe from tank - is petrol leak regular,or only when you release cap?)