540i fuel gauge and RPI questions
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Hey!!
I have a friend with a 2003 540i M Sport. His fuel gauge is giving him some random readings. I.e...... We know it's at a half tank but reads empty then half then empty and so on.......... any ideas??
Also, does RPI make an exhaust for the 540???
Thank You!!!!!!!!!
B
I have a friend with a 2003 540i M Sport. His fuel gauge is giving him some random readings. I.e...... We know it's at a half tank but reads empty then half then empty and so on.......... any ideas??
Also, does RPI make an exhaust for the 540???
Thank You!!!!!!!!!
B
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According to its website, RPI does not make an exhaust for the E39: http://raceprecision.com/2009/index.php?op...51&Itemid=2
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Originally Posted by sdg1871' post='1017231' date='Sep 25 2009, 07:33 PM
According to its website, RPI does not make an exhaust for the E39: http://raceprecision.com/2009/index.php?op...51&Itemid=2
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Originally Posted by bespoke1' post='1017233' date='Sep 25 2009, 08:36 PM
Guess not!! Thanks for the link! I guess when I get my RPI he will just have to suffer in his pitiful jealousy!!!
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Originally Posted by sdg1871' post='1017234' date='Sep 25 2009, 07:40 PM
Well Brian, I am always a little jealous when I hear an E60 with RPI exhaust. The sound is sick.
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My Ride: 2008 550i Jet Black on Black Leather, SAT with Paddles, Logic 7, Comfort Seats, NAV, Sport Package, PDC, Xenons, Sirius, Trinity 12W LED Angel Eyes, RPi GT Exhaust, M rear spoiler, ACS Roof Spoiler, Tinted Tail Lights, Bimmian Carbon Fiber Pillar Trim, Bimmian Shadow 550i emblem, RPi Scoop, E60 Forum Cling, Mtec bulbs in fog lights, Mtec 2W LED for License Plate Light Bulbs, K&N Filter, Bimmian LED Smoked Side Markers, Blackout roundels, Carbon Fiber Kidney Grills.
Retired Rides - 1989 325i convertible, 1995 M3, 2002 X5, 2005 545i, 2008 X5 (Lemon)
On my old E36 M3, the fuel gauge was difficult too! 
I would fill the tank and it WOULD NOT register on the gauge until I pulled out a fuse for 30 seconds, and THEN it would read correctly. BMW never figured out exactly why this was so. They theorized it could be gas additives coating the sensor in the tank, and that was why it read erroneously. BTW, they did replace the sensors twice and it still didn't solve the problem! 
I would fill the tank and it WOULD NOT register on the gauge until I pulled out a fuse for 30 seconds, and THEN it would read correctly. BMW never figured out exactly why this was so. They theorized it could be gas additives coating the sensor in the tank, and that was why it read erroneously. BTW, they did replace the sensors twice and it still didn't solve the problem!
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Originally Posted by flyingpuck' post='1017240' date='Sep 25 2009, 07:50 PM
On my old E36 M3, the fuel gauge was difficult too! I would fill the tank and it WOULD NOT register on the gauge until I pulled out a fuse for 30 seconds, and THEN it would read correctly. BMW never figured out exactly why this was so. They theorized it could be gas additives coating the sensor in the tank, and that was why it read erroneously. BTW, they did replace the sensors twice and it still didn't solve the problem!
I would fill the tank and it WOULD NOT register on the gauge until I pulled out a fuse for 30 seconds, and THEN it would read correctly. BMW never figured out exactly why this was so. They theorized it could be gas additives coating the sensor in the tank, and that was why it read erroneously. BTW, they did replace the sensors twice and it still didn't solve the problem! 
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My Ride: 2008 550i Jet Black on Black Leather, SAT with Paddles, Logic 7, Comfort Seats, NAV, Sport Package, PDC, Xenons, Sirius, Trinity 12W LED Angel Eyes, RPi GT Exhaust, M rear spoiler, ACS Roof Spoiler, Tinted Tail Lights, Bimmian Carbon Fiber Pillar Trim, Bimmian Shadow 550i emblem, RPi Scoop, E60 Forum Cling, Mtec bulbs in fog lights, Mtec 2W LED for License Plate Light Bulbs, K&N Filter, Bimmian LED Smoked Side Markers, Blackout roundels, Carbon Fiber Kidney Grills.
Retired Rides - 1989 325i convertible, 1995 M3, 2002 X5, 2005 545i, 2008 X5 (Lemon)
I obviously could still drive the car even with this little flaw, but it was annoying! 
I would suggest pulling the fuse related to the gauges for 30 seconds and see if it resets itself! 
Let me know how it all turns out! 
I would suggest pulling the fuse related to the gauges for 30 seconds and see if it resets itself! Let me know how it all turns out!
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Originally Posted by flyingpuck' post='1017255' date='Sep 25 2009, 08:00 PM
I obviously could still drive the car even with this little flaw, but it was annoying! I would suggest pulling the fuse related to the gauges for 30 seconds and see if it resets itself! Let me know how it all turns out!
I would suggest pulling the fuse related to the gauges for 30 seconds and see if it resets itself! Let me know how it all turns out! 
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Originally Posted by bespoke1' post='1017261' date='Sep 25 2009, 09:07 PM
I will. I like that 540. Very different from the E60. But, it's nice.
Exact same problem I had years ago.
On my e39, I replaced the fuel sending unit, fuel pump, etc. and no help.
It turned out to be what BMW calls a "jet pump". Basically a siphon tube. Very cheap part
The e39 has a split gas tank over the drive train. Normally the gas just sloshes around in both parts, but the fuel pump is only on one side. The siphon tube or "jet pump" moves gas back over to the fuel pump side when it all sloshes to the other side. Sometimes they get clogged.
That would be my guess.