I replaced the pump this morning, and the problem got worse. Not a cheap pump, I used the pierburg, and now it does it even more. I'm thinking the old pump was wearing out, but now that the fuel flows better through it, perhaps there is an issue with the injectors? ( the change of speed happens I try to give it gas after switching a gear ) someone said clean out the injectors using "sea foam or similar product? man, I'm fresh out of ideas, having replaced everything this thread has suggested!