fatboycowen 31 #1 Posted October 8, 2019 Well, I check this forum daily, wishing for more 5xi content. I guess I should be careful what i wish for. My 518xi has been nearly flawless. But, recently, it starves for fuel when I drive up a somewhat steep hill (which i have been going up for years). I also noticed that on hard left turns (especially on pavement - smart steer disabled, she pulls some Gs), it does the same. I haven't done extensive testing yet, but it seems to happen on left turns (iirc), and not right turns... It seems like simply fuel starvation. It cuts out, but sputters a bit first. It's not immediate. In turns, if i stop moving, or straighten the wheel, she comes back to life before fully stalling. On the hill, if it dies, i simply roll back to flat, and she starts right back up. The first time, i was getting low on fuel. So i added fuel and was able to drive up the hill normally. But, it will stall in turns with 3/4+ tank. I haven't fully tested this on the steep hill. Some research suggests it could be multiple things. I'm looking for ideas for the next steps to take in diagnostics. My next steps: - Fuel filter - Fuel pump - Check fuel lines for pin holes - Carb seal kit (float may be clogged) - wiring - look for things shorting in these conditions - fuel tank - look for a blockage. Any other ideas? Items to check first? Things i shouldn't bother with? Thanks! Share this post Link to post Share on other sites
gwest_ca-(File Mod) 11,450 #2 Posted October 8, 2019 Check this out Garry 1 Share this post Link to post Share on other sites
doc724 925 #3 Posted October 8, 2019 My money is on the fuel pump. I had a 520xi. If you shut it off when it was warm, it would not restart for 4 hours. One day I had the bucket full and it just stopped. Dumped the dirt, had it towed back into the garage. Next morning it started without any problem. Changed the fuel pump and never had a problem. Fuel pumps were $22 at that time (2016) Share this post Link to post Share on other sites
BESTDOGEVER 218 #4 Posted October 8, 2019 I recently had my fuel filter crushed on my 518h and the symptoms were quite similar check the fuel line routing Share this post Link to post Share on other sites
fatboycowen 31 #5 Posted October 18, 2019 So, I found the problem. Here's how it went. First, i looked at all the lines. Nothing was pinched. Line to the carb is ugly, but i didn't have a replacement (ordered). Changed the fuel filter, and the diaphragm fuel pump (cheap). Next, i tried it. The pump pulled some fuel into the filter slowly, but it quit when the carb bowl ran out. I disconnected the fuel line from the barb at the tank. Mine has a metal shut off valve at the tank exit. The valve was barely trickling fuel when open, nothing when closed. I removed it, and fuel gushed out. Emptied the tank into a container. The problem was the metal valve. It's the narrowest point, and it had crap in it. Pine needles, and other garbage. I cleaned it, and it flowed well. Reinstalled, and she fired right up. I tried to get it to starve, by doing circles in the driveway in high gear. Couldn't make it starve. I'll do more testing this weekend. So, assuming this metal shut off valve is factory, and you have a restriction, clean this sucker out. It's pretty easy to do, and made a world of difference. I'm planning to change all the lines in the coming weeks. Thanks for all the help. 1 Share this post Link to post Share on other sites
WVHillbilly520H 10,376 #6 Posted October 19, 2019 3 hours ago, fatboycowen said: So, assuming this metal shut off valve is factory, and you have a restriction, clean this sucker out. It's pretty easy to do, and made a world of difference. I'm planning to change all the lines in the coming weeks. Thanks for all the help. Yes those tank shut off valves are factory but normally come with a bronze in tank screen... You may want to replace it as well check this out... https://rover.ebay.com/rover/0/0/0?mpre=https%3A%2F%2Fwww.ebay.com%2Fulk%2Fitm%2F291551135450 1 Share this post Link to post Share on other sites
