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    Arivera112's Avatar
    Arivera112 Posts: 16, Reputation: 1
    New Member

    Feb 20, 2008, 07:19 PM
    Water in gas tank?
    Any suggestions on how to remove water from gas tank? We have a 2005 Lexus that when the tank gets below 1/4 tank, it hesitates. How do we know if there is water in the gas tank? How do we fix it? Thanks in advance!
    N0help4u's Avatar
    N0help4u Posts: 19,823, Reputation: 2035
    Uber Member

    Feb 20, 2008, 07:50 PM
    You sure it is water in the gas tank?
    You can go to Advanced Auto, Pep Boys or some auto parts dealer and buy some dry gas and follow the directions.
    If it isn't water in the tank you may need a fuel filter.
    kitch428's Avatar
    kitch428 Posts: 1,428, Reputation: 152
    Ultra Member

    Feb 21, 2008, 04:25 PM
    If water is in there, then misfires will occur. This will flash the check engine light while the hesitation is happening. Is this what's going on?
    Here's what I would do. Run the fuel as low as you can. The dealer can then run the pump with their scanner and pump out the remaining contaminated fuel, take samples, and add fresh gas. Should be about an hour shop charge.
    kitch428's Avatar
    kitch428 Posts: 1,428, Reputation: 152
    Ultra Member

    Feb 22, 2008, 04:21 PM
    this8384, could be true. It depends on the amount of h20 in the tank. The poster says the problem starts at the 1/4 mark on the fuel gauge.
    I've seen many vehicles in my time fuel up at some of the crappiest gas stations and get massive amounts of h2o in there. And IF the gas station has close to empty tanks, guess where THEIR water is.
    Should have said 'could' instead of 'will'. My bad there, but take a minute to read my bio sometime. In the past twenty something years with Toyota, yeah I've seen a misfire or 2.

    Cap'n, feel free to chime in here!
    CaptainRich's Avatar
    CaptainRich Posts: 4,488, Reputation: 537
    Cars & Trucks Expert

    Feb 26, 2008, 02:31 PM
    Kitch is correct here. Water can and will cause a misfire, particularly at the volumes the OP is stating.

    I've once stopped for gas and then couldn't get out of the station. That much water won't respond to the bottle-in-the-tank remedy. You will likely need to have the tank pumped and possibly flushed, depending on how much water is in there and for how long.
    this8384's Avatar
    this8384 Posts: 4,564, Reputation: 485
    Ultra Member

    Feb 27, 2008, 04:13 PM
    Come to think of it... they're claiming it only hesitates when the fuel drops below 1/4 of a tank. If there's water in the fuel, it would most likely be running bad all the time, no? We're all dead-set on this "water in the fuel" idea, but they haven't really defined how it's "hesitating." Could be a number of things, now that I really sit back and think about it...

    Anywho: kitch, I apologize for my "disagree"; I wasn't trying to imply that you're not qualified in any way, shape or form. It was kind of a knee-jerk reaction because I hate it when I hear about people dumping more money into their car than they need to. I didn't feel that all of that was necessary as the problem wasn't consistent; it just seemed like they'd be paying a whole bunch of money for something that wasn't a necessity at this point in time.
    kitch428's Avatar
    kitch428 Posts: 1,428, Reputation: 152
    Ultra Member

    Feb 27, 2008, 08:54 PM
    The original poster needs to come back and stop being so shy. Here we go again with the help us to help you speech.
    I asked the OP in my first post, "is this what's going on"? I'm used to the shyness around here, but not the disagrees.
    That being said, the vehicle in question is a Lexus. These people are used to their cars running 100% all the time. They truly are great cars and I enjoy working on them and helping with any problems.
    Arivera's 2005 Lexus has water in the fuel tank. I'll be willing to bet it's a minimal amount and the gauge has to be just above empty to show up any hesitation.
    When a Toyota/Lexus client says their car hesitates, 9 out of 10 times they mean it's misfiring, or the throttle by wire lag time. Lol

    This is for you, Arivera112 or anyone else with similar issue. Just a little FYI:

    When a misfire occurs in the engine, hydrocarbons (HC) enter the exhaust in high concentrations. If this HC concentration is high enough, there could be an increase in exhaust emissions levels. High concentrations of HC can also cause to temperature of the catalyst to increase, possibly damaging the catalyst. To prevent
    this increase in emissions and limit the possibility of thermal damage, the ECM monitors the misfire rate.
    When the temperature of the catalyst reaches a point of thermal degradation, the ECM will blink the MIL.
    For monitoring misfire, the ECM uses both the camshaft position sensor and the crankshaft position sensor.
    The camshaft position sensor is used to identify misfiring cylinders and the crankshaft position sensor is used to measure variations in the crankshaft rotation speed. The misfire counter increments when crankshaft rotation speed variations exceed threshold values.
    If the misfiring rate exceeds the threshold value and could cause emissions deterioration, the ECM illuminates the mil.

    If the misfire cannot be reproduced, the following reasons may apply: 1) the vehicle has low fuel, 2) improper fuel is being used, and 3) the ignition plug is contaminated
    jennyrene's Avatar
    jennyrene Posts: 20, Reputation: 6
    New Member

    Feb 27, 2008, 10:35 PM
    You can pour alcohol in the gas tank and it will cause the water to dissipate. But that may not be your issue. Your car would sputter a lot and not just on 1/4. I'm just a girl you know but it sounds like the fuel pump.
    ingird41's Avatar
    ingird41 Posts: 2, Reputation: 1
    New Member

    Aug 8, 2010, 07:34 AM
    I had water in my gas tank. I got the fuel fileter replaced followed by the fuel pump. Last night the before the mechanic brought my car to me, he stated he has to rewire the fuel pump in my buick and when I got ready to leave work, my lights started going dim and my car stopped. I got the car restated and it died out again, this time the whole electrical system went out and now my car is not starting at all, what has he done to my car, please someone help me?
    ingird41's Avatar
    ingird41 Posts: 2, Reputation: 1
    New Member

    Aug 8, 2010, 07:36 AM

    kitch428 can you give me some sound advice ***?
    TxGreaseMonkey's Avatar
    TxGreaseMonkey Posts: 16,758, Reputation: 5596
    Uber Member

    Aug 8, 2010, 07:42 AM

    ingird41, test all under hood and under dash fuses with a test light or multimeter:

    Have you spoken to the mechanic?
    kitch428's Avatar
    kitch428 Posts: 1,428, Reputation: 152
    Ultra Member

    Aug 8, 2010, 09:39 AM

    Hmmm, that's a toughy. What did this mechanic do (asking myself) to cause this? Could it be coincidental? But since he was the last one to 'touch' the vehicle, and he brings(?) the car back to you, have him come out and have a look at it. Sure sounds like an electrical issue so have him bring the proper equipment with him.
    stevelastic's Avatar
    stevelastic Posts: 1, Reputation: 2
    New Member

    Oct 8, 2010, 10:04 AM
    I have used a very good product in the past. It was a sock that you put into your fuel tank and it absorbs all the water. Take the sock out a day later and all the water goes with it.
    Bobsgas's Avatar
    Bobsgas Posts: 1, Reputation: 1
    New Member

    Apr 22, 2011, 12:34 PM
    Water is heavier than gas, it sits on the bottom of your tank and the stations. The position of the fuel intake is about a few inches above the bottom of the stations tanks. If the water accumulation is greater than a few hundred litres that is when it is possible to get water to the pump. At the pump there should be filters, so if the pump is very very slow, this would indicate there is a problem with water. The pump would not normally allow any water to pass through it unless the filters are completely full of water (causing it to slow to a crawl). Also, if there is a tanker at the station filling the tanks, that would stir up even small amounts of water so best to wait until the fill is done.

    Gas-line antifreeze, water remover usually helps, and if not get the tank drained and add fresh gas.
    myzellj's Avatar
    myzellj Posts: 1, Reputation: 1
    New Member

    May 8, 2011, 08:40 PM
    You really need to drain the tank. I had to do a job of this type today. Also change the filter, but not always necessary. Then attach everything back,and add an additive for water removal and then add at least 7 gallons of gas. Move to the hood. Remove the gas line from the inlet to the injectors. Unclamp it and place the end in a gas tank. Trun the engine over until all of the water comes out. You will no that the water is gone when you start getting gas. I turn the engine over two or three more times to make sure. Next disconnect the battery and take the injectors out. Clean them all with WD40 until there is no rust visible. Shake all of the extra water from the injector brace. Finally shoot one shot of starter fluid in each injector port and then reconnect everything. Start the engine. Good Luck.
    nissanquest94's Avatar
    nissanquest94 Posts: 2, Reputation: -1
    New Member

    Jun 26, 2011, 08:57 PM
    When your gas tank has water, as long as the water % not exceed certain threshold, your engine will run as if there is NO water; however, when it reach that threshold range, your car will start losing power, hesitate and may stall when start. It often happened to used car with quite a few years, but more importantly with certain number of miles. Here is why?

    For Lexus 05, it may have around 100,000 miles, and each time you fill up gas tank, you may get around 0.1% of water from your gas station, sometimes less with named brand such as Mobile or Shell... etc, but sometimes more with very cheap gas such as Raceway, no name gas,. etc. You can get an idea in gasbuddy dot com. If each fill up gives you 250 miles, you can count that over 400 gas fill, your gas tank may have accumulated to over 4% water which could kill your engine.

    It is NOT deterministic because some people like myself always fill gas at half tank, and it took my Nissan Quest 94 bought at new 17 years to finally hit this water problem because as you can calculate, most of time my gas tank has less % of water as the total fuel and water is high, and accumulated water, often sink into the bottom with lower %. However, for other people like this Lexus 05, apparently fill up the gas tank below 1/4 tank, so for the same amount of water accumulated, his water % may be high and hit misfire problem sooner, in this case, only about 5 or 6 years.

    So the quick solution is to go to name brand gas station and fill higher octane gas, and you will be fine for 3/4 tank of gas. Doing so will give you some more time to deal with it, at least, you do not get more water into your gas tank. You may even ask the gas station to find out when their gas station reservoir to be refilled as the reservoir is also like our gas tank, the heavier water will sink to the bottom, and the lighter gas will be on top. As the total amount in the reservoir decrease, their water % increase that that gives you better chance to obtain more water. In the extreme case, some unlucky people got too much % of water at gas station and could not start the car. After all, your fuel injector spread water vapor that can not be burned at combustion stage when your spark plug fired that unhappy your knocks sensor that tells your ECU to give you "check engine light" ON.

    While you prevent more water coming to your gas tank, you should also get some "dry gas" bottle to remove existing water out of your tank. I used "Heet" yellow bottle, $2 of 12oz treat 21 gallon at Pep Boys, which has methanol which is also heavier to sink down to combine water into burnable acid to be burned out of your gas tank. You may also get other brand like "Splash" yellow bottle, 99 cents of 10oz treat 10 gallon if you tend to fill up gas in half tank. As soon as you fill in, you will like myself to magically recover lots of power immediately, you can fill up at your gas tank any time, but if you fill a bottle at 1/4 or lower gas left in your tank, you feel more impact. I also used STP red bottle "gas treatment" that also have some power of "remove water" for new car preventively.

    So, as you can see, if you have the knowledge mentioned above, you shall NEVER got hit, say, got too much water in your tank, because it is the matter of water %, unless you got hit by accident got too much water at cheap gas station at their almost empty gas reservoir. All you need to remember is at which level of your gas tank that you start seeing the misfire problem, and treat it, i.e. remove the water with above mentioned "water remover". There are other brand like Techron that also claim to treat fuel line... etc but much more expensive like $10. I never used, but since you can afford expansive car like Lexus, $10 probably is not much different from $2 or 99 cents to you, but I optimize everything to achieve high enough power I need.

    If you understand the fuel inside your gas tank is NOT homogeneously stored, gas lighter always on top and water heavier always on bottom, you should also see that in your fuel line, they are also flow this way, and in cold winter time or area, your water line may be freeze, and that's why the above mentioned products also claim to be "antifreeze" because when methanol combine with water to become burnable acid, the freezing point became lower, not to be frozen below 32 degree F, or your fuel line may become narrower, and your fuel filter may be partially block, and your fuel pump may have to work harder, and all related sensors may behave odds. So, if you take your car to auto mechanics, they may get crazy, very happy to replaces all these parts to make good money from you.

    Now, you may also find that in the cold morning, when you start the engine, it may either hard or may stall, while once start and warm up for 10 or 15 minutes, it runs normal and through out the day, it start good and no problem, till next morning. It is because the threshold of water % is NOT fixed, it is temperature dependent. In other words, your engine can tolerate LOWER water % at lower temperature, once started the engine which may went up to 230 degree F, the threshold becomes higher and your engine can tolerate much higher % of water in your gas tank.

    I wish I have answered all your puzzle on this non deterministic engine stall, loss power, misfire, check engine light on... problem. And, it is very easy to resolved over time, as this problem often occur over time. A quick solution is always get your water pump out at once, but as you can see 4% of water in your gas tank of 20 gallons is less than 1 gallon, and when you pump, you can not just pump out water without also getting gas out, and can not be done in 100% water, but that may be good for many years.
    STEVE75's Avatar
    STEVE75 Posts: 1, Reputation: 1
    New Member

    Jul 15, 2011, 03:45 AM
    What the best why to get water out of your gas tanks
    nissanquest94's Avatar
    nissanquest94 Posts: 2, Reputation: -1
    New Member

    Jul 15, 2011, 06:36 AM
    If you got more water, you may find the red box iso-Heet 12oz $1.99 mixes 5 times more water in your gas tank than yellow box Heet 12oz $1.37 at Walmart. For preventive gas treatment, you may find red box STP gas treatment $1.29 very good, every so often when you have long trip may be good to add a box that shall delay your gas tank water problem for years.
    kitch428's Avatar
    kitch428 Posts: 1,428, Reputation: 152
    Ultra Member

    Aug 6, 2011, 07:53 PM
    Check out this turkey Chrysler8 who threw in a comment on post #4 of this thread recently.
    Has no credibility on this forum whatsoever.
    How about spreading some reputation around chrysler8 since you know so much!
    Attached Images
    madfire932002's Avatar
    madfire932002 Posts: 3, Reputation: 1
    New Member

    Oct 18, 2011, 02:57 PM
    ingird41 hey the dumb *** that wired up you fuel pump miss wired it and short circuited your wiring and not every time you start you care you are destroying battery, wiring harness, alternator, and starter. So if I was you I would get hold of you of them and make them fix you car for free if they don't you have a law suit on your hands with them.

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