I have just bought a mondeo astate 2ltr turbo diesel and have noticed that under accelleration from about 2ooo revs it is making quite a loud hissing noise, which stops uppon braking, but can not be heard out of gear whilst reving up!. Dont want to take to dealer as was 100 miles away. Would be grateful for any ideas as to the cause.
sounds like turbo pipe loose or split, check hoses from turbo to intercooler and back to engine, the most commom one is the elbow pipe under the plastic engine cover to the right of the engine. pipes are about 3-4 inch dia.
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