Who puts premium in their MDX?
05-13-2009, 08:08 PM
#1
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Who puts premium in their MDX?
Yeah, I know another gas thread. I'm getting closer on my deal for an '09 MDX and was just wondering who puts premium in theirs. I will for sure as I have used premium on my past Acuras (TSX and current TL).
05-13-2009, 08:11 PM
#2
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Isn't that specifically required in the owners' manual ? regardsless I've done for my last three Acuras as well ... supposedly for better performance as some of the other owners have demostrated through their data collections & analysis ...
Go get your MDX before they run out ... LOL
Go get your MDX before they run out ... LOL
05-13-2009, 09:57 PM
#4
Old Man Yelling at Clouds
I always use what the manufacturer recommends - Premium only in my MDX and TSX. While I'm not an automotive expert, I don't think using lower octane gas in an engine that expects higher is good for the engine in the long run. I understand these engines can compensate, so maybe you just take a hit on the mileage. For me, why mess with it. I figure if I was worried about an extra $2.00 per tank to fill up, I shouldn't be buying an MDX. 
Congrats on the upcoming purchase!
Congrats on the upcoming purchase!
05-14-2009, 02:46 PM
#6
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I always use what the manufacturer recommends - Premium only in my MDX and TSX. While I'm not an automotive expert, I don't think using lower octane gas in an engine that expects higher is good for the engine in the long run. I understand these engines can compensate, so maybe you just take a hit on the mileage. For me, why mess with it. I figure if I was worried about an extra $2.00 per tank to fill up, I shouldn't be buying an MDX.
Congrats on the upcoming purchase!
Congrats on the upcoming purchase!
05-16-2009, 06:43 PM
#7
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It recommends Premium to take advantage of the posted horse power ratings. I drive sensibly and rarely do I need to take advantage of full potential. For both of our X's it's 3 tanks a week or $12/wk x 52 weeks= $604. I'll save the $$ even if both the X's are paid off.
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05-16-2009, 06:49 PM
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You mean $120/wk right ? I want to go wherever you can find me a $12/wk (full tank I assume?) gas station ..... LOL ...
05-17-2009, 11:52 AM
#9
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05-17-2009, 11:36 PM
#10
Old Man Yelling at Clouds
Problems When Using The Wrong Octane
Even though times are tough, skimping on the proper octane for your vehicle’s engine will end up costing you more than what it would cost to fill up with the correct gas over time. Let’s take a look at a fairly common and affordable high performance auto to illustrate the point of what can occur when the wrong type of octane is used. Let us look at a 2001 Ford Mustang Cobra. The Cobra has a compression ratio of 9.9:1, which calls for premium gasoline (91+). If a lower grade of fuel is used, the chances of catastrophic engine problems are more likely. If an owner, for example, repeatedly fills up with 87 octane, early detonation could occur, which can lead to engine pinging or knocking.
Early detonation (or pre-ignition) is when the combustion reaction occurs too early, which does not allow the piston to reach the highest point within the cylinder wall. Engine pinging is essentially a shockwave of sorts within the cylinder from the early detonation. Besides the loss of power, the engine timing is thrown for a loop. Undue pressure can be placed upon the rods under the piston, which can lead to catastrophic failure and an expensive rebuild. Putting too high of an octane in your car will not damage the motor, but it will lighten your wallet unnecessarily. If your car’s motor is designed for 87 octane, it will be unable to use all of the high octane fuel, which will end up leaking out your tailpipes.
Even though times are tough, skimping on the proper octane for your vehicle’s engine will end up costing you more than what it would cost to fill up with the correct gas over time. Let’s take a look at a fairly common and affordable high performance auto to illustrate the point of what can occur when the wrong type of octane is used. Let us look at a 2001 Ford Mustang Cobra. The Cobra has a compression ratio of 9.9:1, which calls for premium gasoline (91+). If a lower grade of fuel is used, the chances of catastrophic engine problems are more likely. If an owner, for example, repeatedly fills up with 87 octane, early detonation could occur, which can lead to engine pinging or knocking.
Early detonation (or pre-ignition) is when the combustion reaction occurs too early, which does not allow the piston to reach the highest point within the cylinder wall. Engine pinging is essentially a shockwave of sorts within the cylinder from the early detonation. Besides the loss of power, the engine timing is thrown for a loop. Undue pressure can be placed upon the rods under the piston, which can lead to catastrophic failure and an expensive rebuild. Putting too high of an octane in your car will not damage the motor, but it will lighten your wallet unnecessarily. If your car’s motor is designed for 87 octane, it will be unable to use all of the high octane fuel, which will end up leaking out your tailpipes.
As with most anything like this, one might argue the Acura engines are sophisticated enough to compensate. Maybe the are - I suppose it depends what you want to risk.
05-18-2009, 05:17 PM
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All three of our vehicles, one of which is an '08 MDX, specify premium so that's what we use. Part of cost of owning higher-performing cars.
I was under the impression that Acura required rather than recommended premium though I'm sure someone will correct me if I'm wrong on that one. They'll still run on lower octane (by law) but you're not supposed to run that way all the time.
I was under the impression that Acura required rather than recommended premium though I'm sure someone will correct me if I'm wrong on that one. They'll still run on lower octane (by law) but you're not supposed to run that way all the time.
05-20-2009, 09:21 PM
#13
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I use 87 in my 04 MDX always...the only time I would pay the extra money is if I was towing and putting a strain on the engine.
05-21-2009, 05:15 PM
#16
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05-21-2009, 06:24 PM
#17
Burning Brakes
05-21-2009, 07:29 PM
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You can put 87 in the tank and it won't hurt anything. The computer will compensate for the lower octane fuel and pull timing as needed and you will have reduced horsepower.
It also state's "recommended" octane and not "required." Reason is b/c there are people who might not read the recommended fuel requirements and put 87 in it. Also for the face that nowadays gas stations also have only 1 pump nozzle per pump which could have some leftover 87 or 89 leftover from the previous person that pumps.
That's the reason these cars have electronic fuel management systems to compensate for the octane difference or weather or elevation and does this to keep the engine from blowing itself up.
It also state's "recommended" octane and not "required." Reason is b/c there are people who might not read the recommended fuel requirements and put 87 in it. Also for the face that nowadays gas stations also have only 1 pump nozzle per pump which could have some leftover 87 or 89 leftover from the previous person that pumps.
That's the reason these cars have electronic fuel management systems to compensate for the octane difference or weather or elevation and does this to keep the engine from blowing itself up.
05-29-2009, 09:13 AM
#19
Chapter Leader (Southern Region)
Why would you skimp??.. your fuel efficiency will drop and once your engine starts to knock.. it's downhill from there. For example, say $0.20 * 17 gallons = $3.40 more.
but on 93 you get 24 mpg vs. 22 mpg on 87.. 408 miles vs. 374 miles. A difference of 34 miles.. that's roughly 1.5 gallons of fuel which just kicked you in the balls because you're actually paying more in the long run and risking detonation / knock.
but on 93 you get 24 mpg vs. 22 mpg on 87.. 408 miles vs. 374 miles. A difference of 34 miles.. that's roughly 1.5 gallons of fuel which just kicked you in the balls because you're actually paying more in the long run and risking detonation / knock.
05-29-2009, 02:13 PM
#20
Old Man Yelling at Clouds
^^ 
The engine was designed for the standard case of using 92 octane. It's an exception condition to use less IMO. I don't think it's good to use any product you buy 100% of the time in an exception condition - especially a car. Sure the engine can compensate but it wasn't originally designed with the expectation that it would have to compensate 100% of the time, year after year. If it was designed with that intent, it would recommend 87 or "anything".
Not intending to insult anyone, but I personally don't understand buying a $45,000 car and then worry about saving $40/month in gas. Buy a $35,000 fully loaded Pilot, pocket $10 grand and run 87 all you like (which is what it takes). Or a Highlander Hybrid if you reallly drive a lot. But, everyone's personal finance is their business. Each to his own.
The engine was designed for the standard case of using 92 octane. It's an exception condition to use less IMO. I don't think it's good to use any product you buy 100% of the time in an exception condition - especially a car. Sure the engine can compensate but it wasn't originally designed with the expectation that it would have to compensate 100% of the time, year after year. If it was designed with that intent, it would recommend 87 or "anything". Not intending to insult anyone, but I personally don't understand buying a $45,000 car and then worry about saving $40/month in gas. Buy a $35,000 fully loaded Pilot, pocket $10 grand and run 87 all you like (which is what it takes). Or a Highlander Hybrid if you reallly drive a lot. But, everyone's personal finance is their business. Each to his own.
05-29-2009, 06:31 PM
#21
Senior Moderator
you can get away with lower octane in the 1st gen MDX, but with the 2nd it's a lot worse. With regular in the 2nd gen, you loose about 2-3 MPG, in the loaner I had and the previous owner put in 87 (saw the receipt in the center console) and I got 2-3 MPG worse than my MDX. When I filled it up with premium it was were it should have been. As well it was sluggish and the car felt a bit rough. In the short run, regular will cost you about the same as premium due to the MPG difference, in the long run it'll cost you more with damage to your motor. Just my 
cents.
Also acurazine does not tolerate any insults of members, the next person to post such will have action take upon them.
cents. Also acurazine does not tolerate any insults of members, the next person to post such will have action take upon them.
06-01-2009, 08:09 PM
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you can get away with lower octane in the 1st gen MDX, but with the 2nd it's a lot worse. With regular in the 2nd gen, you loose about 2-3 MPG, in the loaner I had and the previous owner put in 87 (saw the receipt in the center console) and I got 2-3 MPG worse than my MDX. When I filled it up with premium it was were it should have been. As well it was sluggish and the car felt a bit rough. In the short run, regular will cost you about the same as premium due to the MPG difference, in the long run it'll cost you more with damage to your motor. Just my cents.
Also acurazine does not tolerate any insults of members, the next person to post such will have action take upon them.
cents. Also acurazine does not tolerate any insults of members, the next person to post such will have action take upon them.
06-01-2009, 10:10 PM
#24
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I've never been able to get 2-3 miles more per gallon with premium, let alone do either of my MDX's run sluggish or rough like you claim. I'm getting 23.5 mpg currently with combine city/hwy, with regular, driving over the past 500+ miles in my 06. I've never gotten 26.5 mpg on any tank regular or premium, nor do I believe it to be accomplished unless you are running downhill, so I say prove it and make me a believer.
06-02-2009, 08:58 AM
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I wish I could get the same on the 01, but were lucky to get 20 mpg over the same routes. The only differences that I'm aware of between the two are exhaust and tires.
06-02-2009, 09:47 AM
#26
Chapter Leader (Southern Region)
I've never been able to get 2-3 miles more per gallon with premium, let alone do either of my MDX's run sluggish or rough like you claim. I'm getting 23.5 mpg currently with combine city/hwy, with regular, driving over the past 500+ miles in my 06. I've never gotten 26.5 mpg on any tank regular or premium, nor do I believe it to be accomplished unless you are running downhill, so I say prove it and make me a believer.
06-02-2009, 12:33 PM
#27
Old Man Yelling at Clouds
The '03-06 & '01-02 are different from the transmission to the shafts which is why you may see a difference, including wheel dimensions but that's generally true for any vehicle. If you run anything less than 91 and the fuel starts pinging / knocking.. the input from the knock sensor will have the engine pull timing and inject an excess amount of fuel to cool off the cylinders.. The vehicles have very sophisticated engine management system that will run rich to protect itself. You might be lucky but I guarantee you that you're doing a disservice by not running 91+.. The engine won't always be able pull timing enough once knock occurs and usually it gets worst where more fuel is being dumped yet damage is still occurring.. and then you're looking at either replacing the pistons and rings & honing and refinishing the cylinder walls at minimum or getting another engine, probably the latter.. not only that but if your engine is retarding timing and running a bit rich you also might be doing damage / clogging up your cat's.. which is also a downhill slope.. once it starts to occur it only gets worse until the restriction in the monolith's becomes too great.. seriously all of this isn't worth the extra couple of bucks you save by pumping 87.. I don't mess around.. one bad tank is all it takes.. I pump 93 tier 1 only. Not worth it IMO.
06-02-2009, 01:10 PM
#28
Chapter Leader (Southern Region)
My father on the other hand is cheaper than cheap. I left my RX300 [CR - 10.5:1] back home for my father to drive and he takes it and puts regular all the time (thankfully he hardly ever drives it, prefers the tundra).. I always dump a bottle of octane booster to help but it's futile. It went through two 02 sensors before 30k miles, but no ping / knock.. It still runs but there's no arguing or trying to explain to my father.. you know what I mean?.. lol.
06-02-2009, 01:50 PM
#29
Old Man Yelling at Clouds
06-02-2009, 05:50 PM
#30
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The '03-06 & '01-02 are different from the transmission to the shafts which is why you may see a difference, including wheel dimensions but that's generally true for any vehicle. If you run anything less than 91 and the fuel starts pinging / knocking.. the input from the knock sensor will have the engine pull timing and inject an excess amount of fuel to cool off the cylinders.. The vehicles have very sophisticated engine management system that will run rich to protect itself. You might be lucky but I guarantee you that you're doing a disservice by not running 91+.. The engine won't always be able pull timing enough once knock occurs and usually it gets worst where more fuel is being dumped yet damage is still occurring.. and then you're looking at either replacing the pistons and rings & honing and refinishing the cylinder walls at minimum or getting another engine, probably the latter.. not only that but if your engine is retarding timing and running a bit rich you also might be doing damage / clogging up your cat's.. which is also a downhill slope.. once it starts to occur it only gets worse until the restriction in the monolith's becomes too great.. seriously all of this isn't worth the extra couple of bucks you save by pumping 87.. I don't mess around.. one bad tank is all it takes.. I pump 93 tier 1 only. Not worth it IMO.
06-02-2009, 07:26 PM
#31
Chapter Leader (Southern Region)
Wheels are the same on both 04+ Touring. I've never heard it knock or ping once. If I'm pulling a trailer or boat it always got 93. We've put on almost 80k miles since we bought it and who knows what the previous owner used for the first 50k and it has been our most trouble free Honda to date.
07-06-2009, 02:27 AM
#32
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What Is Octane?
A few others have given good info on this thread, notably Majofo, but nobody has explained what octane is so far, and I thought I would, since it is usually misunderstood.
Premium gas isn't "more powerful" or such. In fact, it is characterized by a resistance to combustion, and that's it.
Gasoline is made up hydrocarbons, and they are not all alike. Gasoline has a mix of carbon-hydrogen chains with different numbers of Hydrogen atoms. Octane is a chain build like: CH3(CH2)6CH3. You'll note that there are 8 Hydrogens, hence the "oct" in octane. Your fuel also has 6, 7, 9, and 10 hydrogen chains.
It so happens that octane is the alkane with the best resistance to detonation by pressure. In an engine, octane really requires a spark to ignite, where other alkanes would detonate just from the compression. So a gasoline with more octane is better suited for high compression engines - it will wait for the spark plug to arc and then ignite. Lower octane fuels will ignite just from the compression.
This pressure-based detonation is actually how diesel engines work, but it's not good at all for gasoline engines. Running too-low octane in a gasoline engine will make it sound a bit like a diesel, called pinging or predetonation.
It will occur at times of high compression, like when you are opening the throttle and putting a lot of air in the cylinders, and the engine is pushing a lot of power, but there is resistance (a trailer, a hill, acceleration). Running a higher octane fuel will impede the predetonation.
So you bought an MDX? You get 300hp out of a 3.7 liter V6. My Dodge Dakota has a 5.9 liter engine that pushes just 258hp! Nothin is free: Your V-Tec engine has high compression all the time, because that's how it gets more power out of a smaller powerplant than a V8. Now you need to pay the piper, throw down the extra cash and buy premium gas. That's the right choice.
You can, as others have said, run Regular. And unlike sports cars of days gone by, which you could tell didn't like Regular because they pinged like crazy, your MDX's computer will compensate for the Regular gas. It will retard your timing to reduce the power your engine is producing thus reducing the compression. Your car computer isn't "making the most of the fuel it's given", but instead is "reducing power output to mitigate severe long-term damage".
If that sounds like something you want to do, be my guest.
Moil4gold49.
Figuring you guys wouldn't trust a noob, you can look up some of this info here:
http://www.consumerreports.org/cro/c...tane/index.htm
Premium gas isn't "more powerful" or such. In fact, it is characterized by a resistance to combustion, and that's it.
Gasoline is made up hydrocarbons, and they are not all alike. Gasoline has a mix of carbon-hydrogen chains with different numbers of Hydrogen atoms. Octane is a chain build like: CH3(CH2)6CH3. You'll note that there are 8 Hydrogens, hence the "oct" in octane. Your fuel also has 6, 7, 9, and 10 hydrogen chains.
It so happens that octane is the alkane with the best resistance to detonation by pressure. In an engine, octane really requires a spark to ignite, where other alkanes would detonate just from the compression. So a gasoline with more octane is better suited for high compression engines - it will wait for the spark plug to arc and then ignite. Lower octane fuels will ignite just from the compression.
This pressure-based detonation is actually how diesel engines work, but it's not good at all for gasoline engines. Running too-low octane in a gasoline engine will make it sound a bit like a diesel, called pinging or predetonation.
It will occur at times of high compression, like when you are opening the throttle and putting a lot of air in the cylinders, and the engine is pushing a lot of power, but there is resistance (a trailer, a hill, acceleration). Running a higher octane fuel will impede the predetonation.
So you bought an MDX? You get 300hp out of a 3.7 liter V6. My Dodge Dakota has a 5.9 liter engine that pushes just 258hp! Nothin is free: Your V-Tec engine has high compression all the time, because that's how it gets more power out of a smaller powerplant than a V8. Now you need to pay the piper, throw down the extra cash and buy premium gas. That's the right choice.
You can, as others have said, run Regular. And unlike sports cars of days gone by, which you could tell didn't like Regular because they pinged like crazy, your MDX's computer will compensate for the Regular gas. It will retard your timing to reduce the power your engine is producing thus reducing the compression. Your car computer isn't "making the most of the fuel it's given", but instead is "reducing power output to mitigate severe long-term damage".
If that sounds like something you want to do, be my guest.
Moil4gold49.
Figuring you guys wouldn't trust a noob, you can look up some of this info here:
http://www.consumerreports.org/cro/c...tane/index.htm
07-06-2009, 07:37 PM
#33
2017 TLX AWD Adv FBP/EB
We do. I did the experiment. Highway driving you don't notice as much 2-3 MPG. It was the city driving, we noticed a 4-5 mpg drop based on her driving. She fills up 3X a month, so the extra $10 is worth it in my opinion. I don't mess around with my RL. I drive hard so the I expect the same or worse drop.
07-07-2009, 03:06 PM
#34
Chapter Leader (Southern Region)
We do. I did the experiment. Highway driving you don't notice as much 2-3 MPG. It was the city driving, we noticed a 4-5 mpg drop based on her driving. She fills up 3X a month, so the extra $10 is worth it in my opinion. I don't mess around with my RL. I drive hard so the I expect the same or worse drop.
07-07-2009, 08:11 PM
#35
Senior Moderator
I've never been able to get 2-3 miles more per gallon with premium, let alone do either of my MDX's run sluggish or rough like you claim. I'm getting 23.5 mpg currently with combine city/hwy, with regular, driving over the past 500+ miles in my 06. I've never gotten 26.5 mpg on any tank regular or premium, nor do I believe it to be accomplished unless you are running downhill, so I say prove it and make me a believer.
07-08-2009, 01:53 PM
#36
Not intending to insult anyone, but I personally don't understand buying a $45,000 car and then worry about saving $40/month in gas. Buy a $35,000 fully loaded Pilot, pocket $10 grand and run 87 all you like (which is what it takes). Or a Highlander Hybrid if you reallly drive a lot. But, everyone's personal finance is their business. Each to his own.
The MDX is a luxury vehicle, not some mass market car that caters to the LCD. People buy the MDX for its combination of luxury + performance + features + SUV. If you can't afford premium gas, you shouldn't be driving an MDX.
You can, as others have said, run Regular. And unlike sports cars of days gone by, which you could tell didn't like Regular because they pinged like crazy, your MDX's computer will compensate for the Regular gas. It will retard your timing to reduce the power your engine is producing thus reducing the compression. Your car computer isn't "making the most of the fuel it's given", but instead is "reducing power output to mitigate severe long-term damage".
If that sounds like something you want to do, be my guest.
If that sounds like something you want to do, be my guest.
Yes, gas is expensive, but in the long run you will find it more expensive not to follow directions.
07-08-2009, 09:52 PM
#37
2017 TLX AWD Adv FBP/EB
I am happy with her, extremely fun to drive, but haven't met an Acura I didn't like yet.
08-14-2010, 09:44 PM
#39
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nice forum - great source of information!
just bought a used 06 MDX today and can't wait to pick it up next friday.
wanted to find out more about gas preferences and found this thread. i've had exactly the past experience that arx-01b indicates with my previous car (2.5L Jag X-Type) using regular. no pinging which i think says no damage. still very good performance. difference in mileage was not measurable.
just bought a used 06 MDX today and can't wait to pick it up next friday.
wanted to find out more about gas preferences and found this thread. i've had exactly the past experience that arx-01b indicates with my previous car (2.5L Jag X-Type) using regular. no pinging which i think says no damage. still very good performance. difference in mileage was not measurable.
