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2001 Outback Limited
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Discussion Starter #1
Hi!
I have a 2001 that I recently bought. It has no codes showing. It seems to run fine until I take off hard making a left turn from being stopped. Really a pain when I have to turn left in traffic. It only seems to do this below 3/8 of a tank of gas. I filled it right after I had this problem, It took 10 gallons and the problem went away. Anyone have any ideas what to look for? I would be nice if it ran until at least the low fuel light came on.:( Feels like it is out of gas. If I straighten out and let it coast or sit for a minute, it runs fine again.
Thanks
 

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03 H6 OBW & 06 WRX Sportwagon
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hmmmm, you symptom is not typical of a compromised cap/o-ring on the fuel pump. Might be worth inspecting it.

Also, i have read of a 'jet pump'/'venturi pump' device that is in our fuel tanks to push fuel from the left side to the right side for pump pick-up. But if that item was clogged, it would seem a RIGHT turn would cause a stall. Also, do you ever notice a vacuum or any whooshing when you remove the gas cap?

anyway, might be worth running a can of SeaFoam through a tank of fuel in case something is partially clogged.
 

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Lawn ornament XT
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Doesn't the '01 have a fuel filter under the hood? maybe it's gunked up and you aren't getting enough fuel pressure overall.
 

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2001 VDC/SC One of a Kind
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The fuel level sensor is on the pump side, so if its registering fuel at the gauge, the transfer pump is working to move the fuel. We can assume the level gauge works if 10 gallons fills it up and is not just a stopping point the OP uses.

Filling the tank up submerges the pump in fuel. There very well may be a leak in the pump assembly that is allowing for air to be sucked in at lower levels. Sharp left, fuel in the tank shifts away from the pump, pulls up air.

Pulling the pump takes about 10 minutes, after you've taken everything out of the way to fold the bench over. Look for a cracked hose at the base of the pump or a separated pump housing.
 

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The fuel level sensor is on the pump side, so if its registering fuel at the gauge, the transfer pump is working to move the fuel. We can assume the level gauge works if 10 gallons fills it up and is not just a stopping point the OP uses.
There could be a problem with the venturi transfer pump, although I've read about this happening only once in a Subaru. (A venturi transfer system is used in other makes as well.)

The fuel gauge indication is based on two tank sensors, one on each side of the car, wired in series. (See attached wiring diagram.)

The sub-sensor (on the left/driver side) has a resistance of around 62 Ohms, while the main sensor (mounted with the pump) is around 32 Ohms. Together, when both sides are empty, the total resistance is about 95 Ohms, and when full, around 5 Ohms.

If the transfer pump isn't working properly, using the example here, there could be a few gallons of fuel in the left side, while the right is near empty. The right side sensor, at near empty, would be at around 30 Ohms (I'm ball-parking), while the left side might also be around 30 Ohms. This would give a total of 60 Ohms which would put the gauge below half full, but not as low as 1/4, which corresponds to the "below 3/8 of a tank".

The right turn/left turn difference could be due to the location of the pump in the right tank and how fuel, at the bottom of that side, moves during these maneuvers.

I would be nice if it ran until at least the low fuel light came on. Feels like it is out of gas. If I straighten out and let it coast or sit for a minute, it runs fine again.
It should, but the low fuel light is turned on when the microprocessor in the instrument panel detects the total resistance above a certain point (probably in the 80-85 Ohm range). So, again, it's possible for the pump to be sitting in an empty area while there's still fuel in the other side, and the total resistance of the two sensors won't trigger the low fuel light. (This is only a suggestion as to what could happen.)

After the gauge gets down to 3/8 full and you experience the hard left turn stall, have you ever continued to drive (perhaps avoiding hard left turns) until the gauge gets down to 1/4, 1/8?

I'm not saying the venturi transfer system is the problem, but if the pump is going to be pulled as cardoc suggested, do so when the gauge is down around the 3/8 indication, and also pull the transfer pump pick-up and sub-level sensor unit on the left side to see if there's a lot more fuel in that side of the tank.
 

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03 H6 OBW & 06 WRX Sportwagon
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if he meant it held 10 gallons when measuring 3/8 tank, could be the transfer pump (didn't know what it was called)

I know the gauge isn't linear, but maybe he IS running out of fuel because some isn't getting moved over.

still, as you say, worth inspecting the fuel pump.
 

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06 Outback 2.5i, 05 Outback Limited
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I had a very similar problem with my 94 Bonneville. Corners with less than a half tank of gas would cause the engine to stall until the fuel sloshed back. In my case, the strainer on the fuel pump was collapsed and wouldn't hold enough fuel to prevent stalling when the gas sloshed in corners. A new strainer fixed my issue.

I'll preface this by saying I've never been in an Outback fuel tank -- is it possible that the baffles in the tank have degraded?
 

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2001 Outback Limited
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Discussion Starter #8 (Edited)
Thanks guys.
I will have to pull the pump and check that out. I had the fuel filter under the hood changed, did it before and did it after the change. By the way, what do I have to do to get at the pump?
Thanks again
Dick
 

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2001 Outback Limited
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Discussion Starter #10
Thanks for the video, I'll remove the pump and check it out. I assume the other fuel level sensor is on the left side similar to the pump on the right? But, Wouldn't making a hard left turn cause the fuel to slosh over the the right hand side where the fuel pump is?
 

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2001 Outback Limited
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Discussion Starter #11
Just had another thought. I just bought this car from someone I didn't know. As you know, there was a lot of water in NJ during the storm. Is it possible he filled the tank and got part gas and part water. Sloshing water around the pickup would make it sputter just like running out of gas. This would also cause the simptoms on a hard left turn instead of a hard right. When I take the pump out, I'll check the tank for water.
Couldn't hurt
 

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Wouldn't making a hard left turn cause the fuel to slosh over the the right hand side where the fuel pump is?
Perhaps, but that would depend on how long the turn takes, the design of the internal baffles, and how low the fuel is in the left side.

Sloshing water around the pickup would make it sputter just like running out of gas.
If there's water in the tank, it would have an impact even when going straight. The pump pickup is set low down in the tank (it's fixed in position at the bottom of the pump assembly) and the tank is shifting in different directions all the time. But even if during a turn the pump would pick up water that otherwise it didn't reach, it would take some time for the water to make its way to the engine where it could cause stalling. It's unlikely to reach the engine during a quick left turn, given that first there has to be the centrifugal force of the turn to move the water to the pump inlet, and then the time for it to be pumped to the front and injected in to the cylinders.

But this is just my way of seeing things. It will be interesting to learn what you find.

And yes, the other fuel level sensor, and the transfer pump pickup, is on the left side.
 

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I faintly recall hearing about someone installing a fuel filter backwards or an off brand filter that caused fuel starve issues. I don't see how a stall at the turn would be caused at the fuel pump end of the system given if air is sucked into the system at the fuel pump your stall wouldn't happen till your a couple hundred feet down the street after making the turn.

Thinking something closer to the engine is causing this or perhaps not engine related at all - drive line binding up forcing the stall.
 

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Check for loose floppy wires under the hood. The stall could be electrical caused by a wire moving and grounding out. Or a loose ground wire causing the electrical system to bonk etc.

Air sucked into the system at the fuel pump end would cause a stall or stumble a decent distance down the street from where the event that caused air to get sucked into the system
 

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2001 Outback Limited
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Discussion Starter #15
When I take off on a left turn, It takes off like a shot. Just as I get to the traveling lane on the other road, it dies. About 3 to 5 seconds.
 

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It only seems to do this below 3/8 of a tank of gas.

if this is true, its a transfer pump, fuel pump/fuel presure/'delivery' or possibly evap/tank pressure-type problem. I don't see how it could be driveline or intermittent electrical/cable short or open.
 

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Discussion Starter #17
I'm going to have to drive it for a few days to get the fuel level down to where it acts up again. Then start checking.
 

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I'm going to have to drive it for a few days to get the fuel level down to where it acts up again. Then start checking.
I suppose I left out one possibility.

Do you have a good feel for what your mileage is? If so, you should know about what range you have. perhaps, you're just running out of fuel because the gauge is lying. Of course, your report of putting in 10 gallons instead of, what? - 13 or w'ever, kinda negates the empty tank/lying gauge idea.
 

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2001 Outback Limited
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Discussion Starter #19
OK, I got the tank low enough to die on left turns. Took out the left side sender and pickup for the jet pump. The left side of the tank is full to the level of the hump in the middle of the tank. So, it appears the jet pump is not working. It was too cold out outside to take apart the right side. I was afraid I would break the plastic fittings on the hoses. I took off the hose from the right side and blew through it and fuel did come out of the pipe it had been connected to. This was with the tank cap on. Could this mean the main fuel pump is getting weak and not having enough fuel going through the return line to make the jet pump work? Again it took just about 10 gallons to fill it up.
Thanks
 

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again, it would be a newly reported symptom but, you really should (when warmer and safe to do so) inspect the cap/o-ring on the fuel pump assembly. i 'suppose' it could be leaking/bypass just enough to do as you suggest and interfere with the jet pumps operation.

If there was no debris blocking the pump's intake OR its outlet, seems like pressure from the pump is the only issue left to check-out. I'd inspect all the internal hoses for cracks too i guess?
 
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