I hope someone can please help me as I'm running out of ideas. My Diesel has a whirring noise in time with the engine revs. It still does it with the drivebelt removed. It's not the turbo . With a stethoscope the noise is definitely coming from the region of the egr cooling valve, but the valve has no rotating parts. It also has pressure when the oil cap is removed but nothing from the dipstick hole. It runs perfectly and doesn't smoke. . The injector washers have been changed. Any suggestions gratefully accepted thanks
