The siphon jet pump really only matters when you are below about a third of a tank (guess on the exact number there). So if you keep your tank filled at half way or higher, and you still have problems, that should rule out the siphon jet being the only problem you have.
If keeping the gas tank > 1/3 full means the problem goes away, then it reappears if you let it get below that, that would be a very simple and conclusive test that the siphon jet pump is faulty. Andrew Wynn has a great thread on here somewhere with photos and graphics to show you how the pumps and fuel tank work, which should make sense of this.
Here's a good thread on the siphon jet repair, with links to that AndrewWynn thread in post #1:
https://xoutpost.com/bmw-sav-forums/...flon-wrap.html
What brand of fuel pump did you use when you replaced yours? Pierburg was the original manufacturer, bought out by TI Automotive, so either of those are good. The loss of fuel pressure after shutting down may be an important clue. I think the pump has a check valve in it, so loss of pressure may indicate a problem with it holding pressure.
03-26-2021, 09:04 PM
Threaded Mode
