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

bill118bill118 Posts: 3
My car is 2006 sonata GLS I4, do you guys think it is a good idea to upgrade to premium gas?


  • backybacky Twin CitiesPosts: 18,623
    Only if you like paying about 10 cents more per gallon for gas than you need to. The engine is designed to run on regular unleaded.
  • drdonrsdrdonrs Posts: 164
    why oh why would you even consider the proposition to switch to premium? The engine is controlled by a computer chip and is set for regular gas. Be happy that it is what it is. Even my Azzy also runs on regular. Of course you might want to make Exxon/Mobil and the other oil companies a little richer and your wallet a little thinner by an unnecessary switch.
  • bhmr59bhmr59 Posts: 1,598
    Gee, you're lucky if you can get by wasting only 10 cents per gallon. In my area of CT the difference in price for premium is 20 cents per gallon. ;)
  • jacknzonejacknzone Posts: 82
    Hi Bill118
    You may like to look at (Hyundai Sonata Real world MPG Numbers ) on page 61 #303
    I found it was around about the same , I'm back using 91 octane, 95 is a $1.529 a litre here . :D
  • patpat Posts: 10,421
    Seems to me that provides the definitive answer.
  • joe97joe97 Posts: 2,248
    Regular unleaded.
  • patpat Posts: 10,421
    Then, as noted earlier, it's only a waste of money to burn premium. The engine is not built to take advantage of it as everyone has noted.
  • I have a 2007 Sonata Platinum ediiton. In the manual it says 87 or 89. I've been using 87 but have noticed minor engine knock. I took it to the dealer and they said this was normal, and will decrease over time since the car hasn't been broken in yet(I only have 700 miles on it).

    My wife recently(a few weeks ago) bought a 2007 Elantra SE. She mistakingly filled up with 89 one day. She told me of her error, and I told her next time use 87. When she filled up the next time with 87, she and I noticed the minor engine knock that my car had been experiencing. Not sure if this is how all Hyundia's are supposed to sound since these are our first Hyundia's. But I'm gonna fill up next time with 89 and see if my engine runs better.

    Any suggestions/experiences?
  • You could try 89 octane but that is still a couple cents more than regular. With regard to the "knock" there should be none on either car using regular. There is, on both cars, a knock sensor that constantly fine tunes the timing and retards it if it detects any detonation (knock). It has been a very long time since new cars "knocked" so maybe what you hear (although it is hard to hear it inside) are the fuel injectors activating. They tick or click all the time and are audible at idle.
  • I took a second look at my maunual and it says for the 2007 Sonata that gas of octain 87 or higher can be used. So i filled up with premium yesterday, and i'll let you guys know if I notice any difference.
  • Sure, you can use any grade gas but Hyundai sets the minimum when they state 87 octain. The "or higher" part of that statement is purely optional (Hyundai is NOT saying you can't use it) so, yes, you can spend more for premium but I,like others here,say it is a waste of $$$.
  • bj02176bj02176 Posts: 115
    It may be a waste of money on the bigger engine, but not on th 2.7 awd, try 89 or higher and see if you do not feel more confident merging on rt 128 with it versus 87. No better gas mileage however.

    I thought they were saying in the manual to use 91 or higher for better performance, I could be wrong, but I think that is what it says in mine, and a true statement if that is indeed what it says.
  • targettuningtargettuning Posts: 1,371
    At one time we owned a 2002 Santa Fe with the 2.7 V-6 and AWD. Since I don't own it any longer I can't do the test you suggest but I never used anything other than 87 in it and don't recall any reason I should have upgraded to 89. I personally don't belive the minor increase in octane from 87 to 89 makes any appreciable difference in vehicle performance and ,for sure, none in fuel economy. It is, especially now, a waste of money for the vast majority of new cars owners. In fact, since probably 98% of all new cars are designed for regular (87 octane) and run perfectly well with it I can't understand why three grades are still available. Aside from some high end luxury cars, some luxury SUV's and very high performance cars premium (92 octane) is pretty much unneeded. You may gain optimal performance with those engines designed for premium if you use it but I'll bet not 1 in 100 Corvette owners could tell the difference if they used mid-grade instead and "lost" a few hp because the engine management computer "dialed back" a few design parameters because of it. Those engines are so massively powerful anyhow nobody would notice.
  • bj02176bj02176 Posts: 115
    I think they retuned the engine, however if you want to merge on rt 128 with just using 87 be my guest, around town the sluggish 87 is fine, but for highway merging 89 alternated with the next higher grade performs best. Just get the bigger engine and be done with.

    Or get a CRV 4 cyl which I believe will accelerate just as well as 2.7 hyundai on 87, and better gas mileage to boot.
  • bhmr59bhmr59 Posts: 1,598
    My '05 SONATA with the 2.7 V6 accelerates very nicely at 87 octane; it's designed to run on 87 octane. No need to spend the extra $.10 per gallon for 89 octane. I've never had a problem merging into traffic, even accelerating up to 80 just because some inconsiderate driver wouldn't back off for 2 seconds to let another car in.

    But then maybe your rt 128 is a different rt 128 than somewhere else, wherever rt 128 is.
  • targettuningtargettuning Posts: 1,371
    Thanks for your input but I fail to see the point of the post for the following reasons:
    1. I don't and never have merged on Rt 128 and I don't even know where it is.
    2. I have never stated I am or was unhappy with the performance of the 2.7 V-6 we had owned. Since we no longer own it it is a moot point.
    3. I am not in currently the market for a car "with a bigger engine" OR a Honda CR-V. I wasn't asking for your or anyone elses opinion about which car or engine I should buy.
    This started out to be my opinion about the uselessness of using a higher grade fuel than stated by the manufacturer and somehow now I have an argument about merging on Rt 128?
    If you feel better about your merge using premium by all means..go for it!!
  • While filling up, I recently discovered that my 07 Sonata Limited doesn't have an "inner" door at the top of the gas tank filler neck. On all the other cars I've owned, I'd see a metal "door" that covers the filler neck once the gas cap is removed. I believe that door functions to prevent gas from the tank from splashing out. Can anyone who owns a 06 or 07 Sonata verify whether the inner door exists for me? Thanks in advance!
  • bj02176bj02176 Posts: 115
    I thought this was about premium gas, you did mention a Santa Fe 2.7, I said the same retuned engine in a 2007 with more horse power gets better acceleration with 89 or higher.

    Around town 87 may be okay, not on the highway. 128 is in Boston, it's the same for merging on any highway in a major city which Boston is.

    The manual for my 2007 says for better performance use 91 or higher, I find it to be true.

    Whether or not you own the car you are still saying other than 87 is a waste, on most cars it probably is, not on this particular Hyundai in my opinion.
  • No "inner door" here, either. I'm not certain, but I think those were put in as an anti-theft/siphoning measure. Gas theft used to be a big problem. Probably too much work for thieves now, they steal directly from the gas pump by driving off without paying. Or use stolen credit cards. Anyway, no need to worry. Enjoy your ride.
  • bhmr59bhmr59 Posts: 1,598
    The topic here is "Hyundai SONATA premium gas."
Sign In or Register to comment.