Howdy, Stranger!

It looks like you're new here. If you want to get involved, click one of these buttons!

Hyundai Sonata Fuel and Fuel System Questions



  • Thanks, wanna_azzy, for checking things out for me! I doubt the purpose of the "inner door" is for theft prevention, though. I think thieves can still siphone the gas given that the door is there, much the same way that the door can be pushed in (to open) when you insert a tube, e.g., the gas pump nozzle. I remembered reading somewhere--from my Intrepid manual (?)--that the door is referred to as a splash guard of some sort, but I could be wrong. Anyhow, it's good to know that I'm not missing anything. Thanks again!
  • targettuningtargettuning Posts: 1,371
    I think that inner door or flap a couple of inches or so down inside filler neck was originally a functional feature that prevented leaded fuel filler nozzles (which were larger) from being inserted in "unleaded only" vehicles. Since unleaded fuel nozzles are slim only they could be used. Now long after leaded fuel has disappeared this feature has also, it seems, disappeared. That said I haven't bothered to look on our 2006 Civic to see if still has one but if it does I don't know the current function. Couldn't be splash back prevention, at least while filling because the door is open at that
  • That flap is only a splash guard to prevent gas from sloshing out while the car is in motion. An anti-siphon feature would be a mesh screen in the filler neck that lets gas in as you fill up but blocks a hose inserted down the opening.
  • targettuningtargettuning Posts: 1,371
    The splash guard idea would only be necessary if someone filled the tank to over-capacity (and only even then until you burned off a gallon or so) plus the screw on cap seals the tank and makes it a closed system for emission reasons. Over capacity is, not only filling the tank but also filling the filler tube to the top. Since this is a no-no with modern cars one shouldn't be doing it anyhow. So I am still at a loss to explain that flap...if it is still there on the newest cars and apparantly the 2007 Sonata (at least) doesn't have it. Maybe it is finally being phased out?
  • bj02176bj02176 Posts: 115
    Which could be my next vehicle if I swith to a sedan, if it doesn't run well on 87, then I will go with Honda or Toyota.

    I was responding to someone with a Sante Fe that posted on this forum with 2.7 engine.

    If you don't like my posts, don't read them.
  • patpat Posts: 10,421
    But the point that this is not a discussion about the Santa Fe is a valid one, so it would be best to just let that go here, no matter the engine. There should be a Santa Fe Real World MPG discussion where these things could be pursued.
  • my 04 sonata has a metal flap at the top of the neck ,of the tank .I thought it was to stop gas vapour or fumes escaping before and after filling your car up, why I say this , is because the Flap is on a spring .
    91 oct V 95 oct or 87 V 89 Oct
    I think for myself it's a waste of money to use higher octane than you need too !
    I posted this in March (Hyundai Sonata Real World MPG)page 16 #303
    I have put it to the test , Four weeks on 91 oct and four weeks on 95 oct ,got a average 22 mpg 91 oct and the same for the 95 oct , city driving / Trip computer average speed 32 kph / AC on. There was no noticeable different in performance .65 litres per tank 5 cents different in price between91/95 Using 91 for me over a year is a saving $85.00
    And I still using 91oct I think the best way to save money on the gas,is in the way we use our right foot.

    The Test is to try it out for yourself ,using the different Octane and the way you use your right foot. :D

    Cheers Jack
  • ms090870ms090870 Posts: 9
    I have a 2001 Sonata. The car have been incredible as far as dependability and economics. This car has 97000 miles on it and in the entire time that I have owned the car, the only work that I have had to do to this car is to replace a rear wheel hub. So needless to say I extremely happy with my car and will purchase an other car from Hyundai the next time I purchase a new car.

    I am currently having a problem with the filling up of the tank. The pump pops like the tank is full but it of course is not.

    I would appreciate any help you can give me.

    Thank you
  • canddmeyercanddmeyer Posts: 382
    Try another pump. This happens to me on a different make of vehicle once in awhile, but I attribute it to something going on at where I'm getting the gas as it's not consistent. I always noticed the pumps have higher pressure when there are less people fueling up and when the stations tanks are full.
  • patpat Posts: 10,421
    Some personally directed posts have been removed. Let's all play nice. It's too early for the heat to be getting to everyone and too late for cabin fever, is it not?

    Althought it's too hot for my tastes where I am today, no doubt!!
  • packer3packer3 Posts: 277
    There could be a problem with the vapor recovery system in the car
  • jdqjdq Posts: 3
    I was driving down the road one day and all of a sudden my engine cut out. The gas tank was full. After I towed it home I changed the fuel pump, which was unneccessary. I cannot figure it out. When I start the engine there is no smell of fuel in the engine compartment. I have the Hyundai Sonata 2002 4 cylinder. Can anyone help?
  • jdqjdq Posts: 3
    Thanks for nothing
  • lightfootfllightfootfl Posts: 442
    Possibly there are not many people here that have a 2002 mdl, and/or have had this type problem. You can't expect to have answers to every problem every time. I really think some people expect too much from these forums. If there isn't a reply, consider that your problem may be unique to you and your situation. Don't condemn the entire group.

  • njalannjalan Posts: 70
    I second. Ida should have contacted a mechanic, a repair shop or the dealership's service department first to identify and fix the problem and then share the experience here. The priorities got all turned upside down. If all such problems could be resolved in this forum, a whole lot of people would be out of a job and business closed for good.
  • huntet02huntet02 Posts: 7
    We just purchased an 06 sonota in March with 58K on it and I am only getting approx. 20 - 22 MPG. I live 35 miles out in the country and most of my daily work transit is on blacktop highway where the speed limit is 65 mile per hour so I should definetly be getting much better gas mileage since its mostly all highway. The first week I got the car we got somewhere around 24+ miles per gallon but NOW its averaging 20-22 MPG per the dash readout and is its right this is unacceptable.
    I came from driving a '95 Camry that with 246K still got excellent gas mileage; I do realize I'm now in a V6 but this is crazy I could be driving what I really like/want (truck) at this kind of gas mileage.
    I have reported this to Carmax were I bought it from and called my local Hyndai dealer to see what I an do and they are supposed to address this Monday.

    What is everyone else seeing gas mileage wise with these cars?
  • ray78ray78 Posts: 27
    Just traded 2006 LX V6 for a 2009 LMTD. Was getting Consistant 31 to 34 mpg on highway. 06 had 52K+ miles..
  • jlindhjlindh Posts: 282
    We have a 2008 V6 with about 9000 miles. I'm using 0w-30w synthetic oil and the tires are at 33-34 psi. I coast up to stop signs and, in short, do just about everything I can do to save fuel. Our driving is about 70/30 highway/city. Once in a while, we get 25.5 mpg for a tank, more often we're down around 25. The car is rated at 28 mpg on the highway, so depending on how you drive, 20-22 mpg on winter gas might be about right.

    The previous poster did not say what their average mileage would be for an entire tank of gas, but I'd be very suspicious of anyone with a V6 who claimed to average over 30 mpg for an entire tank unless they were doing a constant 50-55 mph.
  • huntet02huntet02 Posts: 7
    I think the past maintenance on my car is an important factor here and maybe it just didn't have all the maint. flushes and things it needed to run right, I think theres a lot of Maint things recommended by Hyundai that have never been done. Carmax where I bought it. put a new air cleaner in it and want me to drive though 3 tanks of gas and then report back to them. I won't let them off the hook. Then their mechanics who we never get to talk to say my bra on the front (thats made specifically by Hyundai) is lowering my gas mileage...BS!! Maybe 2mpg but were off at least 6MPG here....I'm still only getting today 21MPG unnaceptable!!
    My local Hyundai dealership says the bra should not make any difference and that they could run some DG fuel cleaner through it and a few other things that would definetly make it run like it should but it would cost $600+ and I'm out of warrantly at 60K but Carmax will make it right. So when their "new air cleaner" doesn't do much I'll be tellling them it needs to go to Hyundai.
  • jlindhjlindh Posts: 282
    I'm thinking that you might have misunderstood my posting. 25 mpg for an entire tank is doable on my car, but it takes a LOT of effort. If you're using gas with ethanol, don't have the tires overinflated, are in a location that still is selling the winter gas formulation, drive much in the city, don't use cruise control, don't baby the accelerator from a stop, don't try to avoid full stops whenever possible, don't coast up to stop signs and aren't using synthetic oil, 21 mpg might be a reasonable mileage.

    I went so far as to purchase an add on "ScanGauge" to show the instantaneous mileage the car is getting and indicate the best techniques to use. Based on my experience, I would guess that my efforts might be netting 3 mpg above my former driving style.
Sign In or Register to comment.