Here is the fuel pump/sender info as from below.
04-11-2002, 07:01 AM
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Here is the fuel pump/sender info as from below.
The fuel tank in All Wheel Drive (AWD) vehicles is divided into two chambers. The electric Fuel Pump (FP) unit (with fuel pump) -1- is in the right chamber. Pump -2- is designed to empty the left chamber -3-.
The Fuel Pump (FP) not only delivers fuel to the engine, it also operates the secondary fuel pump.
For this, it creates an operating stream that is pressed into the secondary fuel pump via a jet which causes acceleration. This acceleration causes the fuel in the left chamber of the fuel tank to be drawn into the right chamber of the fuel tank.
In this way, the left chamber of the fuel tank is emptied first, so that there is always enough fuel in the right chamber for the Fuel Pump (FP).
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20-107
Disturbances caused by a defective secondary fuel pump
If the secondary fuel pump -2- is not functioning, up to 15 liters of fuel -3- (up to about 1/4 of tank capacity) can remain in the left portion of the fuel tank that cannot be drawn out by the Fuel Pump (FP).
If the vehicle will not run due to lack of fuel although the tank is about 1/4 full, proceed as follows:
The Fuel Pump (FP) not only delivers fuel to the engine, it also operates the secondary fuel pump.
For this, it creates an operating stream that is pressed into the secondary fuel pump via a jet which causes acceleration. This acceleration causes the fuel in the left chamber of the fuel tank to be drawn into the right chamber of the fuel tank.
In this way, the left chamber of the fuel tank is emptied first, so that there is always enough fuel in the right chamber for the Fuel Pump (FP).
--------------------------------------------------------------------------------
20-107
Disturbances caused by a defective secondary fuel pump
If the secondary fuel pump -2- is not functioning, up to 15 liters of fuel -3- (up to about 1/4 of tank capacity) can remain in the left portion of the fuel tank that cannot be drawn out by the Fuel Pump (FP).
If the vehicle will not run due to lack of fuel although the tank is about 1/4 full, proceed as follows:
04-11-2002, 07:10 AM
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That only tells part of the story
I have now gone through 9 FSU's on my car including the 2 that came with it. I know exactly how much fuel is in my car based on the location of the needle on the fuel gauge and the miles driven.
The times I have run out of fuel the gauge has read anywhere from 3/4 FULL to empty. It didn't make a difference. The issue is not getting all of the fuel out of the drivers side part of the tank, but the sending units reporting an inaccurate reading to the instrument cluster.
Each time the dealers has found either the float arms were bent, or the FSU's were not getting the correct voltage or the FSU's themselves were just broken.
What you are saying would make sense if your gauge was never erratic and you ran out of gas multiple times all at 1/4 tank left. That has never happened to me, nor anyone else that I could think of that has had FSU issues.
Since my FSU's have gone once again, when I bring the car in I will have them not only replace the FSU's and cluster I will have them check both fuel pumps just for the hell of it. Thanks.
The times I have run out of fuel the gauge has read anywhere from 3/4 FULL to empty. It didn't make a difference. The issue is not getting all of the fuel out of the drivers side part of the tank, but the sending units reporting an inaccurate reading to the instrument cluster.
Each time the dealers has found either the float arms were bent, or the FSU's were not getting the correct voltage or the FSU's themselves were just broken.
What you are saying would make sense if your gauge was never erratic and you ran out of gas multiple times all at 1/4 tank left. That has never happened to me, nor anyone else that I could think of that has had FSU issues.
Since my FSU's have gone once again, when I bring the car in I will have them not only replace the FSU's and cluster I will have them check both fuel pumps just for the hell of it. Thanks.
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