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Hi all!!

I drive an STS -93 and my problem is that the engine stalls at low level in the fuel tank.
It appears with less than ¼ of fuel in the tank, but only when turning right. I also sense that the engine doesn’t work generally proper at the low level.I read somewhere in this forum that early fuel tanks had some problem. Now I have replaced the tank into one from an STS -94. Furthermore I have installed new fuel pump with filters, but the problem remains. Anybody who knows what can be the problem and not only advice to keep the tank full?

Finally; where is the chime (indicating lights on, or key in the lock when door is opened) located under the dash board?

Tank's
 

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I believe there are baffles in the tank which help to keep the fuel accessable to the pump at low levels. I have heard of these breaking loose in the tank allowing the fuel to slosh around during turns which could cause the pump to starve at times. Someone correct me if I am wrong here.

You have stated that you've changed the tank and pump so that may not be the issue.

I imagine you have replaced your fuel filter, it might not make too much difference unless it is highly restricted by debris.

Have you checked your fuel pressure regulator for leaks?

You should get a fuel pressure gage, attach a length of hose with a fitting on the end to connect to the schrader valve on your fuel rail, tape the gage to your windsheild so that you can observe it while driving. Drive the car with the tank at various fill levels and check the pressure. It should remain somewhere in the 30-45 psi range. If it does not then you have a problem with either the fuel pump (still), regulator or restriction in the lines.
 

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Thanks Kev

You mention loose baffles, there is any baffles at all in this tanks -93 -94,they was complete empty, what I could see! Maybe that is the problem!?


All fuelfilters are replaced and I have a new FPR with no leaks, I hope :)
But I can't see why this could be the problem, the problem only occur when the fuel level is under 1/4, with half tank and above the car runs fine.

Maybe there is something wrong with the "fuel delivering unit" in the tank ?
 

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First of all....
It is not good for any electric fuel pump to operate at low fuel levels. Since the gasoline also acts as a coolant for the pump, it is necessary for it to remain submerged. To continually run on fumes is asking for electric fuel pump failure.

Refilling the fuel tank when the needle shows less than a half tank is always a good idea. Adding 5 gallons to an almost empty tank is a very bad practice. I just told my son the very same thing. If you can't afford to keep your fuel tank full, you can't afford to drive a car...period!
 

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Tex,
I was of the same belief but was once told that it is actually the fuel flowing through the pump that cools it. I'm not sure which is true but that does make sence or there would likely be many, many more bad pumps. I do agree with your theory though, but personally use 1/4 tank as a bench mark.
 
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