We just purchased a punto evo 1.3 jtd from 2010 with around 30,000 miles on the clock. After driving it for a couple of weeks we noticed a quiet hum coming from the engine that rises and falls with engine revs that's present in all gears. The hum is also present if the car is stationary, out of gear and the engine is revved.

I read somewhere that 1.3 jtds all have this characteristic and that the noise emanates from fuel travelling through the fuel pipes. Has anyone else had experience of this with their 1.3 jtds or knows where the noise could be coming from?

Thanks!