I've got a Mercedes AMG 2001, with a PO410 code. I changed the smart pump, checked the one-way valve, relay and fuse. All pipe holding vacuum on the EGR valve is new. Pre and post cat sensor have been decarbonized and smoke tested, but it still has the code. Bad fuel consumption has been causing problems. What could possibly be wrong?
You’ve changed the check valve. Unfortunately, on those things, the pumps themselves are often what go wrong. And as expensive as those things can be, you’ll probably need a new pump on that thing.
What you might try to do is see if you can find either a remanufactured one which is going to be a little bit cheaper or see if you can find a used one on a salvage yard, because these parts are so expensive that it’s not something you’d really want to do.
If you can’t deal with it, call the YourMechanic technicians and they will be able to source a better part for you and save you some money on that. Because pros like them and myself are doing that all the time, this is something that we are used to doing. We are used to looking for car parts like that and we know where to find them. After you get the part, they can help you install your EGR valve for you so that you can be sure that it is done correctly.