We only use Aisin pumps, they are the same as the ones Toyota supply. If you compare one of our pumps to a Toyota one side by side, they'll look exactly the same. When did you guys buy the pump (roughly)? We must have sold over 40 of these, I've used them myself a couple of times too. Can you send me a couple of pictures where it's fouling so I can show them to our supplier please? Cheers Idrees ID-Workz