Regular vs Premium Gas

From reading the manual, it's my understanding that you're supposed to fill the Micra with regular gas. However, my dad has been encouraging me for months to fill up with premium instead because it's better/cleaner for the engine and also helps with fuel economy (you get a tank of gas for longer than with regular). I have noticed that after filling with premium, I do get a bit better mileage.

Is it okay to fill a car with premium even though the manual says regular? My dad has been driving for a long time and I do consider his opinion but I wanted to get some other opinions. He's pretty adamant about only filling the Micra with premium.

Hi astroz0mbies,

I have had my Micra a year and 3 months, very low milage car not quite to 9000km yet. Up until last week i always filled up with premium. There have been a few heated debates here on the forum on the premium/regular question and after looking on line at a bunch more info, debates and technical discussions, i have decide to try running regular gas to see if there is any difference i can notice with regards to mileage or performance.

I am at a little over half a tank and so far no noticable difference anywhere (except the price).

For my self.i always put 91+ octane because it get a bit more range and its cleaner. No ethanol in there.

You won't hurt the car putting in premium.

The small improvement in fuel economy is probably not as big as the cost difference.

If money's no concern, don't worry about it.

follow the manual

putting premium on an econobox like our Micra is gonna do nothing but 1) empty your wallet faster, and 2) produce a psychological placebo effect on you

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Originally Posted by micrapolis

follow the manual

putting premium on an econobox like our Micra is gonna do nothing but 1) empty your wallet faster, and 2) produce a psychological placebo effect on you

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^This

Don’t Waste Money on Premium Gas if Your Car Is Made for Regular

But using a higher octane fuel than a vehicle’s owner’s manual specifies “provides no increase in fuel economy, horsepower or a reduction in emissions,” said Greg Brannon, the AAA’s director of automotive engineering.

The extra octane acts as a catalyst for combustion in a high compression engine. If the manual doesn't call for premium don't waste your money!

If you look in your owners manual it says 87. But looking for 91. So im using 91 oct

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Originally Posted by n15sk4

If you look in your owners manual it says 87. But looking for 91. So im using 91 oct

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If it states 87, why put in 91?

Dude, take a look at Micra's oil filter, it's 1/3 size of a regular oil filter. A large size lawn mower has a bigger filter than our Micra's engine. Our tiny 4 cylinder engine don't need premium gas.

For your information premium vs regular will always be a debate its like syntec vs mineral oil.

If you dont know the oil filter is the same as a qr25,qg18,vq35,vq37...

91 all day every car. 87 is piss poor gas and if you dont have en electric motor getting you going you're just gonna burn through more gas when you push the car. Dont flip flop though, use one or the other and let the engine learn the fuel trim. I strongly recommend warming up the engine I find I get way better gas millage when I let my car warm up for quite a while.

I've filled up my Micra with premium and found no significant improvement.
The engine still knocks with either fuel type.
With 91, the Micra started up on higher revs sooner than the 87.

I'm rolling with what the user manual calls for. I bought this car from its original owner, he used to run our Magna fuel (87 octanes). I think our (as in Mexico) user manual calls for 91 octanes, Wich would be our Premium fuel. Yup, we only have those 2 options. The on board computer had a 11.3 or so km/l average, ever since I started using premium fuel it climbed to 13.8 or so. Besides, our Premium fuel is sulphur free, unlike Magna. Engine's cleaner, O2 sensors should live longer. All this, of course, might only apply on my country. Recently we had a Premium fuel shortage, and I definitely felt a lack of performance, nothing huge or dramatic, but it was there.

The only real difference is no ethanol in 91+. Ethanol is terrible for metal parts, rubber, emissions systems, etc. yet the Micra is made for 87. Put whatever you want in it except Diesel.

Just an update in this thread. I decided to update you guys on what I've personally found with using premium instead of regular gas. For reference, my vehicle is a work vehicle. I'm a nurse who drives to peoples homes and provides care. With that in mind, I do A LOT of driving. While using regular gas, I was filling up twice a week. Since switching to premium, I haven't had to fill as often and my tank lasts me a week or more. (Depends on how busy my schedule is.) That also includes leisure driving.

When did you switch?

One thing to consider is warming outside temperature has a significant impact on fuel economy. Everybody's fuel economy is improving at this time of year, even when no other changes are made.

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Originally Posted by MetroMPG

When did you switch?

One thing to consider is warming outside temperature has a significant impact on fuel economy. Everybody's fuel economy is improving at this time of year, even when no other changes are made.

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I started in January. I remember hearing that winter tires/snow can affect fuel economy (for obvious reasons) so I'll keep an eye on it and see how it goes during the summer.

Not just tires, but different fuel formulation (winter vs. summer blend), increased bearing & drivetrain drag, air density, longer engine warm-up, and a bunch of other reasons. FYI: Why your Micra's fuel economy is worse in the winter

Oh yeah, it was terrible for me this winter. I think the highest I went was 8.4? Now it's down to around 7.3.

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Originally Posted by DirtyMicra23

91 all day every car. 87 is piss poor gas and if you dont have en electric motor getting you going you're just gonna burn through more gas when you push the car. Dont flip flop though, use one or the other and let the engine learn the fuel trim. I strongly recommend warming up the engine I find I get way better gas millage when I let my car warm up for quite a while.

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87 is no more "piss poor" than 91. it has less octane. If you understand combustion, gasoline and thermodynamics. then, you would realize that for the micra 91 is piss poor. 87 octane makes more power, therefore you will get better gas milage, and also, be heavier in the wallet. Same with my Jeep patriot. 87 gets better milage than 91....why? because it makes more power. Look it up sometime before making blanket statements like piss poor gas if you have no idea what you are talking about.

Won't 91 give a few more horsepower on the Micra? I am saying this because Lexus and Acura use similar engines to Toyota and Honda, but they modified the engine or the ecu and it require premium gas for the extra bump in power. I been using regular for a month and premium for a month, and found no difference.

It depends if the car was designed for it. If the car calls for 91 and you use 87, the car will retard timing and you will drop a couple of hp. but its not an inverse reaction with a car going from 87 which is was designed for to 91. you will not gain any hp. Its not using 91 for extra horse power, its using 91 for resisting knock and detonation from higher compression ratios and advance timing. In the micra, 91 is pissing away your money....nothing more. I am a mechanic, and built race engines etc.

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Originally Posted by kojack

It depends if the car was designed for it. If the car calls for 91 and you use 87, the car will retard timing and you will drop a couple of hp. but its not an inverse reaction with a car going from 87 which is was designed for to 91. you will not gain any hp. Its not using 91 for extra horse power, its using 91 for resisting knock and detonation from higher compression ratios and advance timing. In the micra, 91 is pissing away your money....nothing more. I am a mechanic, and built race engines etc.

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Glad to see someone else understands this issue..."money for nothing"!

Thanks...

Yes. I do. and you are welcome.

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Originally Posted by kojack

It depends if the car was designed for it. If the car calls for 91 and you use 87, the car will retard timing and you will drop a couple of hp. but its not an inverse reaction with a car going from 87 which is was designed for to 91. you will not gain any hp. Its not using 91 for extra horse power, its using 91 for resisting knock and detonation from higher compression ratios and advance timing. In the micra, 91 is pissing away your money....nothing more. I am a mechanic, and built race engines etc.

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That's interesting to know. We've got a Ridgeline that calls for 87 octane but 91 if towing in the manual. My other vehicles I've always upgraded the ECU and tuned for 91 octane (Honda/Acura). So until someone, somewhere starts tuning HR16DEs we're pretty much outta luck for seeing any benefits at all from running 91 octane? I've always heard that it's cleaner too but I don't know how much that matters overall.

Living up North I just take care to buy fuel at reputable gas stations versus always using premium. That's something people in rural Canada should definitely watch out for more. Dirty old garbage fuel from one-off gas stations. My partner works in the transportation industry and I get all the intel and horror stories about it lol.

I do however, explicitly use synthetic oil and only put Genuine OEM or Amsoil Synthetic MTF in my gearboxes. It barely costs any more in the long run considering all the other running costs of a vehicle. If you're going to splurge on one and cut cost on the other definitely synthetic oil > premium. Just my .02$.

Its no more clean than regular 87 gas. that is a myth. the ONLY difference is the octane. The ridgeline calls for 91 while towing because it will be creating a lot more heat while towing so the higher octane number will combat this. And yes. Unless it's a turbo etc, tuning pretty well can only advance timing and duration of timing. fiddle with a few sensors but it does not make that much difference it the big scheme of things. But once you start advancing timing, then the need for higher octane goes up.

I am an amsoil dealer and reseller, and swear by it. I have many results where asmoil makes a difference in my customers vehicles and toys. A lot of my snowmobile clients were using iPone oil which has an additive for smell. So, I blended smell additives into my amsoil snowmobile oils and they loved it. Plus I could do more than just strawberry then.

The gas stations here all get gas from the same refinery, and from the same truck...Just buy from the busiest station so you get the fresh stuff.

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Originally Posted by kojack

I am an amsoil dealer and reseller, and swear by it. I have many results where asmoil makes a difference in my customers vehicles and toys. A lot of my snowmobile clients were using iPone oil which has an additive for smell. So, I blended smell additives into my amsoil snowmobile oils and they loved it. Plus I could do more than just strawberry then.

The gas stations here all get gas from the same refinery, and from the same truck...Just buy from the busiest station so you get the fresh stuff.

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That's funny! I didn't know there were scented additives used in snowmobiles and I grew up in Labrador lol.

I heard a lot of testaments from Amsoil advocates in the Honda forums as well and have slowly been converted.
I usually just use Mobil1 synthetic oil (I know, not a TRUE synthetic) but you can actually buy it in 4L jugs at CTire here.
I don't skimp at all on transmission fluid and NAPA has it on hand luckily.

A handful of gas stations here get old dirty oil coming down from Alaska that they don't want.

sounds like our grocery stores...gets all the **** that the mainland don't want..ha ha. Yeah. ipone oil is the only 2 stroke oil with scent, but me being crafty found a product, used in race fuel to mask the smell so you can run it "covertly". So, I said, self, that burns in gas, I called the company and yep...it burns in oil the same way, so I now have blueberry and root beer smelling 2 smokers flying around here! ha ha.

I switched my F150 to completely amsoil products and gained almost 100km extra per fill up. Plus I never changed my oil for 45,000 kms and it was still good. using oil analysis!

Salut groupe je suis du Québec je roule sur une route presque droitde 20klm pour allé travaillé et 20klm pour revenir avec du 87 octane je fais du 5.5l 100klm avec du 94 octane du petro-canada je suis tombé à 4.3l 100klm je roule sûr le régulateur de vitesse à 90klm et si je roule à 75klm je tombe à 3.6l 100klm

Salut Erwin! Ce sont des resultats pour des tanks complets? Conditions meteorologiques identiques?

Oui metrompg je roule toujours avec un plein je ne desen pas à bas de la moitié du réservoir.pour les conditions météorologiques normal en 12° à 28° avec pluie ou pas et un du vent de force faible moin de 15km/h.. l'ordinateur de bord indique une consommation moyenne de 5.7l 100klm
Je suis capable de le descendre à 5.1l 100klm mais j'ai le pied bien pessand en ville comme toute les feux de signalisation sont pas sycroniser.

we drove 370km today, starting with a full tank, filled the tank again and it took 25.78@1.18 per liter. on the dash display it read 411km left in the tank. AWESOME RANGE. gotta love it.

I did 445 kms on 32.733L. Cost me $31.39 to fill up(On 87).

Well if you want to burn non-ethanol fuel and get around 10% better fuel economy, then run 91 octane. That is what I do on all my gasoline powered vehicles, motorcycles and lawn equipment.
Ethanol is hard on all of it. IMO and my mechanics. My mechanic builds hot rod, race engines, etc, etc.

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Originally Posted by Ajijic

If it states 87, why put in 91?

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... the engine runs fine on 87, I found if you put straight premium in it the fuel economy actually suffers a little... the engine from the factory is tuned to run on regular, and that's what it likes. I tried a mixture about 50/50 and the economy improved somewhat.. seemingly to normal... but I would never use premium on a regular basis.. no need

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Originally Posted by MortimerSnerd

... the engine runs fine on 87, I found if you put straight premium in it the fuel economy actually suffers a little... the engine from the factory is tuned to run on regular, and that's what it likes. I tried a mixture about 50/50 and the economy improved somewhat.. seemingly to normal... but I would never use premium on a regular basis.. no need

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All vehicles that are gas will run any grade. They just retard the timing. Its no big deal. Now the EPA admitted that ethanol ruins emissions equipment. Old news: https://www.asphaltandrubber.com/new...engine-damage/

If the car isn't tuned... Regular is the one to pump!

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Originally Posted by GreatWhite

Well if you want to burn non-ethanol fuel and get around 10% better fuel economy, then run 91 octane. That is what I do on all my gasoline powered vehicles, motorcycles and lawn equipment.
Ethanol is hard on all of it. IMO and my mechanics. My mechanic builds hot rod, race engines, etc, etc.

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.... it's my understanding that only a few stations sell gas that does not have ethanol, which I do believe degrades performance a bit. Shell 'V Power, 91 octane.. the $$ premium stuff supposedly has no ethanol.

I live near Manzanillo and I understand Pemex does not pollute the gas they sell here with ethanol, Mexicans like to eat the corn they grow... usually in the form of tortillas. Their regular gas known as magna verde works just fine in my new 2021 Micra automatic, only US $12,000 and badged as a Nissan 'March Sense" here.. standards are far more common here, and about US $1000 cheaper.