fuel problem

[mattcow]

I've been having a fuel problem with my car for the last few months now and I can't say for sure what it is.

The events:
First below freezing day of the year - little to no fuel was being delivered to the fuel rail so I suspected freezing of the fuel line. I put some antifreeze in the line and it started the next day (was above freezing).

2 months later- After putting antifreeze in every tank since the first occurrence (and 2 tanks with water remover), I tried a tank with no antifreeze in it and again the line apparently froze with the same symptoms as the first time.

Today (3 months after the second event) - the weather has been warm for the last 3 weeks and I had not put antifreeze in the tank for 2 tanks. 3/8's the way through the second tank the car would not start. The temp. was well above freezing and there seemed to be some fuel getting to the fuel rail. The car at the time was parked on a slight decline so I moved it to level ground and put in 10 liters of fuel along with some antifreeze. I then kept the car idling with "quick start" in the intake so I could burn what ever was in the fuel line. It took less and less "quick start" as the engine idled until the car idled on its own and it was fine after that.

So it seems as though I have water in the fuel tank and today some water got sucked up which stopped the engine from starting until all the water was out of the line.

Could water stay in the tank for 5 months without coming out?
Or could it be something else; like dirt/debris that gets trapped on the inlet periodically?

Note: The I tested the fuel pressure during the first event and it was fine.

[SE2000]

Time to drain the tank. You won't actually get all the fuel out as there is the inner tank but it's not much so I would not bother dropping the tank to get it all. Maybe your gas station is the culprit.

[mattcow]

If it is water its hard to say where it is comming from. I know I can't drain the fuel tank via the filler tube so should I try to suck it through the fuel pump line?.

[rixGAphx]

I think you need to look elsewhere than at a 'water in the tank' problem. My reasoning:
A. Ignoring the fact that I'm in AZ and don't know water/ice problems from a hole-in-the-ground, it seems very unlikely that you alone would have such massive wter/ice problems.
1) There are many others on here from CN, MI, etc.
2) Unless there's been an epidemic in NB of water-laced gasoline, and your neighbors have similar tales.
B. Even though your previous efforts, using de-icer especially, have been successful, that doesn't mean
1) Water/ice was actually the original problem; or even if that WAS the problem, that,
2) Your present problem, though having same symptoms, has the same cause.

Water is 1 kg per liter, gasoline is 0.65 kg/l, and the two do NOT mix.
Being significantly heavier, water will ALWAYS flow to the bottom of the tank immediately, and be sucked-up ASAP.
And no matter HOW 'empty' you get the tank, the heavier water is prolly gonna stay at the bottom, in the 1-gallon or so 'residue' that you can't reach.

You can 'empty' a GA's tank by disconnecting the fuel outlet at the filter, and connecting a tube that runs to a gas can.
The turn the key 'on' and let the fuel pump do its job of pumping the fuel out.
That will still leave whatever amount of liguid, possibly water, always remains below the FP's pickup screen.

The design of that screen is such that virtually no amount of solid residue could block it.

But personally, to satisfy myself on this issue, I would drop the tank, remove the pump, and inspect/clean the inside of the tank.
You may even have a rusty hole in the top of the tank that allows road water to flow-in and continually contaminate the tank.
IMO, that would be the only way your car can be so continually possessed by water problems.

Good luck,
-Rick

[mattcow]

Thanks Rick, you’re always super helpful!
I was preparing to drop the tank this weekend to check it out but I hadn’t considered your "hole in the tank" theory which is very possible especially since I've had the small evap leak DTC on since last year.

To track down the small evap leak I've filled up the tank right to the top before to see if any gas could be seen leaking out, but I never did see anything. Which leads me to my question:

Is there anywhere in the evap system that would allow/suck water into the tank besides the fittings near the tank (ie. Pump module O-ring, filler tube)?

[rixGAphx]

Not to my knowledge, but I've never had to explore the vapor-recovery system or the return lines to the tank.

The vapor recovery system is just tubes, fittings, charcoal canister, and a few small devices.
I don't recall any tube or device connecting to any coolant-containing tube or engine part.

Kinda hard to imagine a 'pocket' or such (other than the large, flat top of the tank) where water could collect and thus be sucked-in.
Mebbe something under the coolant reservoir, where the charcoal canister is located IIRC, but I've never been under there to see.
* * *

Yeah, with your harsh winters, possible salt on the roads, and the DTC, I'll bet the fuel tank has a rust-thru on the top surface.
Get a line on a replacement.
And get a buddy to help you lower it.
I did mine solo, using some nylon cord to make some 'slings' for lowering/raising, but an extra hand would have helped a bunch.

Good luck.
-Rick

[SE2000]

Now you mention the leak. I had a leak in my Lexus if I filled it. Found out the vent tube rusted. Your more likely culprit is the fuel filler/vent system. Not likely a hole in top of tank.
1 gas station that got a lot of water in it and ran low can affect just a few cars that use that station.