The first super-cold day (29 degrees) about 10 days ago my ride wouldn't start in the morning. I had 1/4 tank of gas. I messed with my Foxwell and activated the Fuel pump a few times and then it turned over and ran perfectly. I filled the tank all the way up per some suggestions here.

It happened again the next day, so I figured the fuel pump was 'failing slowly' like AndrewWynn often talks about. So I replaced the fuel pump with a Pierburg from RockAuto.

Lo and behold, yesterday morning it did the same thing. I have to let the pump prime fully before attempting a start. It works fine like that. If I don't turn the key to accessory and I just slam the key all the way to start on the first start of the day, it will turn over and over and over. No start. Then I just turn the key OFF, back to Accessory, wait for it to prime...and no problems.

I did have a few codes on the Foxwell regarding fuel trim, ignition switch and oil pressure sensor. I reset those and they haven't come back on. They probably will in a few days though. I have seen them before but the car runs perfectly other than a chronic low idle.

My next suspect was the siphon jet pump, but my fuel level reads fine all they way down and the problem occurs both with a full tank or 1/4.

Would love some help troubleshooting! Thanks guys!

__________________

2005 X5 3.0i - 71k mi (9.2018) -> 81k (9.2019) -> 100k (9.2021) -> 123k (8.2025)
---------------------------------------------------------------------
SOLD : 2003 X5 3.0 - 177k mi (9.2018) -> 186k (9.2019) -> 205k (9.2021)
SOLD : 1997 328is Coupe - Hellrot Red
SOLD : 1988 528e w/ Bullseye s256 / MS2 Extra / GC Coilovers / Yukon Coils ~ 300+ HP