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Discussion Starter #1 (Edited)
OK, R level sensor went out and took the dash fuel display with it. Symptoms were: dash fuel level not responding to fill up until car restarted several times, then transitioned to zero fuel being displayed on the cluster a couple of days later.

Opened the cluster and saw: L fuel level reporting normally, R fuel level zero. Replaced the fuel pump and R fuel level sensor. (Fuel pump because it seemed to quit one day going in to work but ran normally on the way home.)

Now: Dash fuel gauge not reporting correct amounts. Sometimes the needle will start out at 1/4 and 30 miles later be up to 1/2. Just filled up because fuel level was showing almost empty, range 31miles, and it only took 9.5USG to fill it up. Now when full, (fuel at top of the filler neck) fuel needle is pointing to just over 1/4 but cluster is reporting 34.0L/25.8R = 59.8Liters = bout 16USG.

I don't know where to start. Fuel gauge seemed to be accurate until the R level sensor went out, now it's gone crazy and does not seem to reflect the level displayed by test #6 in the cluster.

ANY help appreciated!!

Thanks much,
Jim
 

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Could be "sticky" sensors. Fuel cleaners will help degum them for proper levels.
Track where the fuel is coming out of. I think the right tank is the one the fuel pump draws from, so the left drains first. Unless there is an issue with th sucking jet pump (transfer pump from saddle to saddle).
 

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Fuel level reading gone crazy

What brand replacement "Fuel tank Level Sensor" for the right side only did
you choose?
 

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Fuel level reading gone crazy

Could be "sticky" sensors. Fuel cleaners will help degum them for proper levels.
Track where the fuel is coming out of. I think the right tank is the one the fuel pump draws from, so the left drains first. Unless there is an issue with th sucking jet pump (transfer pump from saddle to saddle).
Yep...You beat me to it. That's a good place to start looking.

Run some Techron through the system first and see if it clears up before digging
into the fuel pump system again.
 

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Discussion Starter #5
What brand replacement "Fuel tank Level Sensor" for the right side only did
you choose?
Bought one from ECS Tuning. I have always gotten quality parts from them. I don't have the brand, but will check.

OK, will run some Techron. I don't see how the cluster can be correct, or seems to be, and the fuel gauge wrong???

Jim
 

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As I was curious I looked to see if there was any wiring "tricks" for the senders etc. didn't find any but did come across some similar symptoms.
How's your battery and alternator voltage? Apparently what you describe are some of the symptoms. "Normally" more than just one gauge but with these vehicles...
 

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Fuel reading gone crazy

At 169,000 miles on my 2000 528I, I figured it was time to monitor my fuel pump
for failure.
Pull the lower portion of the back seat out and listen,thats easy. Sound is the best indicator
of a problem "mechanically speaking"; as I have found through the years. And BMW
actually did a design service for us all by putting the fuel pumps under the rear seats
located in the fuel tanks. Such a common failure but easy to hear it happen....!

This to me is a no brainer as a failed fuel pump will just leave you dead on the road.

I actually knew for a month or so that mine was on the way out and I purchased a
a replacement pump only, (SIEMANS) ready to go for the eventual failure that was
to come. No sensors or floats etc.

Sure enough I heard gurgling on the opposite side of the firewall as i was sitting
at idle in a quiet parking lot at work. Pump struggling to get fuel through the lines.

I took a chance and got home without any problems (10) miles and my car died
were i usually park it at home......Barely 200-300 rpms at idle when I parked it.

Replaced it and all is good. Did not mess with the floats or the sensors.

Cheers.
 

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Discussion Starter #8
Alt has been good, batt new. Have a check light, gong to see what that is all about tomorrow or Friday. Can't understand how the cluster can be correct but the gauge wrong.

Jim
 

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Discussion Starter #11
The fuel needle acts almost as if it has been bent. Like when the R side read zero and caused the needle to drop to zero, the needle dropped so low it was bent toward the low side.

Does anyone know, is there anyway to calibrate the needle??? Say, fill the tank to the top then make the needle read full??

Thanks,
Jim
 

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Discussion Starter #13
Think I have it covered, thanks for the check list.

Could pull the unit again and inspect all. Still need to install the fuel filter. Think I'll go into it again this weekend.

Jim
 

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When changing components that affect the outcome of the "hidden menu's" data (which are funtions of the IKE)...remember to do a RESET (which is TEST 21).

See description of TEST 21 in the info below:

 

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Discussion Starter #16
LOL, I think that's it! What would we do without you QSilver7!!!!

Thanks Q and all who have helped me get this fuel thing under control.

Jim
 

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I hope this does solve your issue...it was the 1st thing that popped into mind...but then I thought...maybe not after reading about the possibility of bent gauge needles. :thumbup:
 

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Discussion Starter #18
I hope this does solve your issue...it was the 1st thing that popped into mind...but then I thought...maybe not after reading about the possibility of bent gauge needles. :thumbup:
Nope, don't need to open the cluster, or drill a small hole in the clear plastic face to straighten out the fuel needle, just got back from the parking lot and the test #21 seems to have taken care of that for me. :)

Thanks again, :)

Jim
 

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... just got back from the parking lot and the test #21 seems to have taken care of that for me. :)

Thanks again, :)

Jim
:thumbup: :thumbup: :thumbup:
 
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