Mine requires a new cog due to excessive wear. I can't buy the cog on its own and Nissan want £500 plus VAT for a new vacuum pump. Add £50 for the chain and £60 for a tensioner and it's a very expensive job for a 153,000 mile 2004 car even though it's a T-SPEC model. It looks as if this may be a common fault as these engines reach high mileage.

I remember my father, in the 1960's/70's, sometimes substituting a mechanical fuel pump for an electric pump. Could I do the same with this vacuum pump and where can I find one?