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Acura MDX gas questions

msmasseymsmassey Member Posts: 3
edited July 2014 in Acura
I purchased an '07 MDX two months ago and the manufacturer suggests using premium gas. I started out using premium but have switched to mid-grade. I was wondering if it's okay to use mid-grade and if it will affect my vehicle's performance.


  • upstatedocupstatedoc Member Posts: 710
    This is a topic that has been discussed to death and I think the consensus is it won't hurt to put a lesser grade gas in your tank, you just won't get the optimal performance. For example, I can definitely tell the difference between 89 octane and 93 octane in my '04 MDX. As for the '07, I haven't had a chance to try that experiment since my wife stole the keys. :P
  • skinnytonyskinnytony Member Posts: 121
    I think minimum 91 octane is a "requirement" as opposed to a "suggestion". If I'm right about that I personally wouldn't mess with fuel below 91 octane, particularly on a $40,000+ vehicle. I have read about people who "mix" 93 and 89 octane which is possibly a good savings idea but quite a bit of hassle...
  • tpulaktpulak Member Posts: 44
    The Acura will run on the lower octane(87), but runs best on 91 or above octane. Using the 91 or above is probably a better option because of 2 reasons:
    #1: you get the optimum performance . I also noticed smoother operation, and slightly less noise.
    #2: you get more miles to the gallon. I own an 04 MDX, and I tried to run it with 87 octane , and it ran just fine, but I got only about 11-13 miles per gallon in the city, and 14-18 miles per gallon in the highway. So on a full tank of gas, I ran only 218 miles!! On the other hand ,using the 93 octane, I got about 16-19 miles per gallon in city, and you won't believe this, but I got about 20-26 miles per gallon in the highway!! So a full tank of gas took me some 326 miles(with some gas to spare).

    I recommend you to use 93 octance, or at least 91 octane. You shouldn't use the 87 octane because after all, this is a car costing upwards of 40 grand. :lemon: I mean, this is a tuned V-6. My 1997 camry (V-4) uses the 87 octane, so most of the time, 87 octane is required for small cars/SUVS.
  • mecheng1mecheng1 Member Posts: 161
    Everything else being equal,... higher octane gasoline will not improve your FE.
  • kingtroll1kingtroll1 Member Posts: 9
    Stick with the premium gas as recommended. I've read, but don't recall what the issue is with using lower octane gas, but it can cause problems, besides the "ping". The combustion characteristics of the fuel is different for different octane grades.The engine can compensate for some variations.

    You spent $46k to $50k on the vehicle, why go cheap on the gas? What will happen if you destroy the engine, the warranty might be void? I'd hate to have that bill to replace it, much less the torment from my wife. Yikes.
  • tpulaktpulak Member Posts: 44
    What's FE?
  • tidestertidester Member Posts: 10,059
    What's FE?

    FE = Fuel Efficiency

    tidester, host
    SUVs and Smart Shopper
  • hbateshbates Member Posts: 1
    I would have to say that premium gas goes right along with the fact that the 2008 MDX is Ulev 2. Ultra Low Emissions Vehicle. If you use lesser gas, then Ulev 2 will not be what comes out of your tailpipe!
  • jmpage2jmpage2 Member Posts: 268
    I agree with others. Why would you want to cheap out on gas with such an expensive car with a high performance high compression tuned engine?

    If you average 15,000 miles a year (which is the national average) then you are going to be putting about 900-1000 gallons of gas in this truck every year. The cost savings of going .40 cheaper to get lower octane gas will amount to savings of $300-$400 a year, or maybe $25 a month.

    Spend $40K on a car and then go cheap on gas to save $25 a month and put fuel in that the manufacturer doesn't recommend? Foolhardy! :P
  • jimbo787jimbo787 Member Posts: 3
    i am interested in leasing an 08 mdx . being 6 foot 4 inches, i was wondering if it was possible to remove the footrest . for people with long legs this has to be a problem. it is very difficult to get in contact with anyone from honda regarding this matter
  • hpowdershpowders Member Posts: 4,330
    This has nothing to do with the forum topic. Why don't you re-post your query in the "2008 Acura MDX" thread?
  • sarleksarlek Member Posts: 1
    I have just bought an Acura MDX 2004 model from the US to be used in a country where only leaded gas is sold. Are there any additives I can add to the gas to protect the catalytic converter?
  • maraistmaraist Member Posts: 2
    I believe the issue is that when the knock-sensor detects a knock (due to any high temperature or compression, especially during high RPM or high-torque under low RPM), it will adjust the timing of the vehicle away from an optimal setting. So you not only get less horse-power, but you get less fuel-efficiency. So if you somehow drive the vehicle in a way that avoids knock, your lower octaine fuel may wind up getting you better mileage (since it has a higher energy density than high-octaine fuel). But from what I can tell here, it's unlikely you'll be able to completely avoid even a single knock for a given tank of fuel on the MDX.

    Note also that American Octaine ratings are different than in Europe. American ratings take the average of loaded v.s. unloaded knocking on a reference engine. In Europe they only measure the unloaded rating. So interestingly enough, the American rating doesn't suggest what an unloaded octaine rating a particular fuel vendor may have.. Two gas companies may produce two totally different unloaded/loaded octain rating pair.. Since you get the average of the two, it's blurred. I wish they'd just display them both.
  • dave_nhdave_nh Member Posts: 6
    I have a 2005 MDX. Each year, we (Wife and I) drive round-trip from New Hampshire to California at least once in June and once in December and have been doing so for three years, now (we are retired). Due to the outrageous gas prices, I thought I'd experiment and see if lower octane gas had any observable, deleterious effects on performance and/or mileage. I understand that when the knock sensor retards the spark to keep from pinging, the performance and mileage SHOULD decrease. A performance drop would not necessarily be an issue since even this model MDX provides far more power than we need. Although this "test" is hardly scientific, we have driven the routes enough times and the trip mileage is high enough that the results should be meaningful.

    A few "test conditions":
    * I do the all but a few hours of the driving.
    * From NH to CA is usually straight out I90 - I80 and speeds are usually Posted+4mph.
    * In Ca, the MDX is used for everyday, around the town driving.
    * Coming back, we try and take different routes; we do a lot of sight-seeing.
    * MPG is always calculated by using the on-board computer.
    * Tires are Bridgestone Dueler H/L Alenza running 38 lps pressure.
    * Engine oil is Mobil 1

    Until this June, we had always used 91 octane and the overall trip mpg was ALWAYS 22 mpg +/- 0.5 MPG. Remember, this is an average based on at least 7,500 miles per trip, usually over 8,000 miles per trip. And there was never an appreciable difference between Westbound and Eastbound.

    This trip, I used "mid-range" octane exclusively on the way out and "lowest" octane on the way back (including a trip up Pikes Peak).

    Results vis-a-vis MPG
    * The average mileage going out was 20.4 mpg using Mid-range octane.
    * The average mileage coming back was the same 20.2 mpg using the "lowest" octane..

    Results vis-a-vis performance.
    * NO noticeable drop in performance and I was looking for one.

    Gas savings on this trip was barely noticeable. In some states, the difference between Premium and whatever I was using was substantial (like California), in other states, not all that much. And when I found a station that was selling Premium for LESS than mid-range, the owner told me Premium was not moving well so he dropped the price.

    As always, For What It's Worth,

  • upstatedocupstatedoc Member Posts: 710
    Great post, we have a '04 MDX and get around 22 highway w/ 93 oct (no 91 here)
    What do you figure your net loss or gain was in terms of $$ using 87 vs. 91?
  • dave_nhdave_nh Member Posts: 6
    My guess (unfortunately, I did not keep all of my receipts) is that I probably saved enough over the roughly 8,000 miles to pay for our dinner for two in Ted's Montana Grill in Colorado Springs. Best Bison meat I have ever had!!

    I notice that in our area (Southern New Hampshire), lately, prices are dropping and the difference between premium and regular is shrinking. I will go back to Premium.

    As an aside, I also own a 2001 Mercedes E320 4-Matic. The drop in mileage from using premium to regular is significant to the point where it is more expensive to use regular than premium. Performance also drops off. Clearly, MB squeezes as much out of their engine designs as possible.

  • sfbayersfbayer Member Posts: 11
    Hi Dave,

    Thanks for the information. I just brought a 2008 MDX three weeks ago. I have been using only 91 octane gas and has been able to get 18 MPG around town and 23 MPG highway.

    The price difference between lowest grade (87 octane) to highest grade (91 octane) in California is usually $0.20 which is less than 5% saving. It is clear that the best option is to use Premium gas as there is a 9% reduction in MPG by using lowest grade (87 octane) based on your average 22 MPG using Premium and 20 MPG using 87 octane.
  • hotrodsurplushotrodsurplus Member Posts: 2
    Additives will not help this issue. The lead will render the catalytic converter junk in very short order (it will coat the catalyzing medium). You may be able to remove the catalytic converter(s), but ONLY IF there are no oxygen sensors downwind of the cats.

    If the MDX has o2 sensors downwind of the cats and you remove them, the ECU will cause the engine to run poorly (generally lean or too little fuel which will reduce power significantly and destroy internal components).
  • ireneatlas19ireneatlas19 Member Posts: 7
    How much does it take to fill up the tank on the MDX...is it more or the same if it a newer MDX?

    Does the MDX 2010 eat up the gas quickly?

    I drive mostly highway is the MDX 2010 for me when it comes to gas?
  • fumdxfumdx Member Posts: 7
    The MDX takes up as much as 21gallons and if you cruise on the range is nearly 400 miles. In terms of factory EPA is 16/21 MPG. If you want efficiency get a hybrid.
  • lhhlhh Member Posts: 35
    I am driving my new 2010 mdx around town (lots of stops and starts) and am using premium gas. I am averaging 13. 4mpg (according to the car computer reading). What have others been getting for milage with 2010's?
  • kingfans1kingfans1 Member Posts: 137
    hello ireneatlas19 I have 2010 honda pilot 4wd. the car required octane 87 or higher.. But I have been using octane 91 for better performance or engine. I am getting 20 mpg. 90% highway. I drive 60-65 mph.

    I think 2010 mdx should able to get 19-20 mpg if you drive 60-65 mph highway driving.. but remember your mdx required octane 91..
  • upstatedocupstatedoc Member Posts: 710
    Thread jack-

    kingfans1- how do you like the pilot? Did you drive an MDX before? Will probably replace our '07 MDX with a Pilot.
  • kingfans1kingfans1 Member Posts: 137
    I like my Pilot very much.. It is only 3000 miles.. sometimes I can hear some kind of noise when I press brake.. It is only happen in the morning when the car is cold.. after I drive for couple minutes, and press on the brake, the noise disappear.. I think it is normal.. ( since brakes are brand new, and I don't use a lot of brakes.. ( most of my driving are 90 % freeway).

    the car is very quiet.. I read on the forum, other pilots owner are complaining about wind noise.. I don't hear any wind noise on freeway driving.. i have ex-l model. that ex-l and tourin model have Acoustic Windshield.. so it is very quiet..

    2010 pilot is a great car.. When I am driving it, I didn't feel heavy.. My brother have 2008 4runner 4wd v6.. When i drive 4runner, it feel heavy..

    for now, i am happy with the pilot... I do like acura tl.. I will probably consider in 2 years..
  • kingfans1kingfans1 Member Posts: 137
    your mdx suppose to get 21 highway mile. it still have special break in oil. so you will get better mpg after your first oil change.. If you turn off the fan/AC, drive 55-65 mph, your mpg will increase..

    so far my 2010 pilot ex-l 4wd average 21.9 mpg. 90 % highway.. the car have about 4200 miles..
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