i have a 2002 model c class 200 s/wagon .i need HELP or advice....i have changed 3 air metering unit(secondary pump) ..a lot of water finds its way into the sealed pump....this causes the unit to cease and engine managment light comes on, engine sounds changes and other changes, e.g performance, fuel consumption, etc...how to stop water and can i just block the unit and carry on driving...........otherwise superb car