I own a 99 golf tdi, I have a problem, when I start slowing down to come to a stop, the car judders, making a tick tick noise, and then when I stop it goes quiet again. I wondered if this could be a mass airflow problem.
Another problem I have is when on a motorway, and I reach 70mph, I suddenly lose power, with acceleration drastically reduced, then when I pull off the motorway, the car performs really slowly.
When leaving the car for half an hour or so, and restarting full power has returned again.
I have new plugs and a fuel filter fitted but no change, also I have noticed that I can't hear the turbo whistling noise like I used too.
Any help on either problem would be appreciated, thanks