Hi, I a 109cdi vito 2005. I have been round in circles with Just Answer website for this problem. The van has recently started making a tappetty like sound but this is not present all of the time. When i accelerate it rattles like mad but goes off when i let off the throttle. It seems only to be happening when i use the throttle. I have no fume smell in van nor is there any signs of leakage on injectors. Van recently serviced, removed serpentine belt to see if it was the adjuster but the noise still there. could someone please help as I dont want to have to go to MB and have them strip engine to find out it is not a tappet. Also could this be timimg chain, turbo, exhaust noise. Thanks