Premium vs. Regular Gas

[mazdaspeedemon3]

anyone watch this train wreck?

sorry cant embed video

http://www.cbc.ca/marketplace/episodes/2012/11/pumpfiction.html

[Thrizzl3]

sure let me go fill up with 87 and see what happens :loco

[loki]

you can't just post this and not have an opinion to go along with it

so let's hear it

[mathew.poulos]

I agree about the mid range cars (for example everyones 3 except the Speed folks), but for that guys vette. . . . i think premium is the way to go.

[Cab0oze]

I didn't watch it but I read the article and spent an hour replying to comments to set people straight lol

-edit-
skipped thru the first half of the show, wheres the train wreck?

[Flagrum_3]

sure let me go fill up with 87 and see what happens :loco

Put your money where your mouth is, try regular for a couple of tanks and see what happens ;-) ...I'll bet if your honest you'll notice no difference as the computer will compensate. I'm not saying it won't make a difference but only that you MAY not notice it.

I watched the full video and I think it is pretty accurate, but, they should have also used a car recommended to use premium and repeated the same tests to be more scientific. Anyways, I think the point made was that with a 'Regular gas' car, nothing more then regular gas is needed, EVER, and using mid or premium gas will not improve it in anyway, which I agree with 100%. For premium cars use what is recommended.

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[loki]

Put your money where your mouth is, try regular for a couple of tanks and see what happens ;-) ...I'll bet if your honest you'll notice no difference as the computer will compensate. I'm not saying it won't make a difference but only that you MAY not notice it.

If the cars are being tuned to run on the higher octane gas and you're pushing the limits of timing etc, then yes you'll notice the difference, and I'm talking about the speed3's here on this forum. The computer will not compensate when you go for a nice WOT run.

you'll notice when your rod decides it wants to go for a stroll on the side of the highway.

[Hyperion]

Those people are retarded.

[Reddie1337]

If you run regular in your speed 3 for long enough, your turbo will blow, and the valve actuators with stop working, and it will cost you over 4000 to fix, and Mazda won't cover it. Happened a CX-7 with the 2.3L Turbo in it.

There is a difference, their issue on the video is they just ran 2 e-tests, one right after the other, without giving the car time to compensate for it being changed. I am actually in the middle of doing this experiment. Did an e-test yesterday after 5000 km of regular gas, and now I am going to run premium after this tank is done. So we will see how it is in about a month or two. (After a bunch of tanks)

[Booter22]

i think on the other end as they are testing a car that takes regular and then with high octane. but dont test a car that should take higher octane with regular... im sure someone would have given up there speed 3, GTI, SI, and so on to have the test completed..but at least if your going to do a test on a car.. use a real car. the chevy cruze is a POS. would have been interesting to see them test more cars. 3s, civic, golf, 3 series, what ever. just because one car tests dont show a difference doesnt mean another vehicle with a smarter computer wont either..

and reddie makes a good point. they fill the car then run the test. they should have done the regular fuel tests and drives. put more high test in. then drove it for a bit to let it get in the system. its not going to be in there right away. it will mix with the regular, then in the pump. lines. injectors. so of course there is no difference. but in TV reporter land there is no time to do the actual job and just run through it quickly they end up with this garbage

[Lockdown]

If you run regular in your speed 3 for long enough, your turbo will blow, and the valve actuators with stop working, and it will cost you over 4000 to fix, and Mazda won't cover it. Happened a CX-7 with the 2.3L Turbo in it.

There is a difference, their issue on the video is they just ran 2 e-tests, one right after the other, without giving the car time to compensate for it being changed. I am actually in the middle of doing this experiment. Did an e-test yesterday after 5000 km of regular gas, and now I am going to run premium after this tank is done. So we will see how it is in about a month or two. (After a bunch of tanks)

What? :loco

[rzapata]

Wow, what a biased way of telling people not to use premium gas on your car that requires premium. That older guy driving the vette is talking horsecrap (modern cars have a lot of engine management technology and tunes it....changes timing - I don't know how vettes work but I disagree with that statement). To think that he's an "expert witness." Why not get an opinion from somebody who's actually tested fuel combustion in engines?

Although, this guy presents his argument in a way, showing that all cars are identical and that's a constant that never change. I would accept it more if he had a variety of cars and still came to the same conclusion. Only thing he got right is the thing about people putting "premium" gas in their cars that only require "regular" gas.

Also, a lot of hearsay and opinions from regular people, not exactly in the know on how their own cars work.. A nice documentary for people who have less knowledge to abide by easily...

PS: 87% clean, 89% clean, 91% clean... Good stuff! :loco

[silverstarmazda]

the only thing accurate about that video is that regular 87 cars dont need premium. thats it, all of a sudden all cars dont need premium. that video is gonna get a lot of complaints wen something bad happens. they dont talk about the other cars that need higher octane or nothing. they just got one guy who says he puts regular in his vette wen it calls for premium. thats just one guy thats not taking care of his car. vettes like that arnt that expensive and can almost guarantee that he blows through cars like no tomorrow. yes probably has this video has saved people from spending too much. but is also telling people who have cars needing higher octane fuel to put in the wrong fuel. marketplace did not do full research or consult multiple automotive specialists/enthusiasts.

i cant believe that "teacher" is actually a teacher.

[Booter22]

now. correct me if im wrong and if i had a speed i would know better. but is not the whole purpose of premium ( apart from the obvious to reduce knock and what not) but doesnt it also help to reduce internal engine temps/ wear and in a car that does not require premium can result in predet?

im sure if you put regular in a speed you will get all sorts of knocks and pings, anyone ever make that mistake?

[vinnierap]

Heres a crazy thought. Use the gas that is recommended by the people who make the car. My car called for premium, I use premium. When I had my dodge ram, cavalier, intrepid i used regular 87 octane. When I had my R6 I used 91-94 octane. Now I have a speed and I use 94 octane (occasionally 91, but only if im in a jam and I have to).

Cars that reccomend 87 octane, only need 87 octane. Putting higher than what is reccomend is not benneficial to the car and thats what i think the video was saying.

[jonjon72]

Cars that reccomend 87 octane, only need 87 octane. Putting higher than what is reccomend is not benneficial to the car and thats what i think the video was saying.

Until they got to the "expert" with the Corvette who stated that premium is recommneded for his car but has decided to go regular because the cars computers compensate for the change.

[rzapata]

Until they got to the "expert" with the Corvette who stated that premium is recommneded for his car but has decided to go regular because the cars computers compensate for the change.

Maybe the vette is actually self tuning... :chuckle

[Lockdown]

I don't think Chevy has spent much time with the self learning. Only a handful of OEM have anything in production that do more than retard on knock.

[Reddie1337]

What? :loco

Which part is what? I have heard so many different stories, I am testing myself. To see if there is any difference to running regular vs premium. And the CX7, we had a customer screw their turbo over by running regular. Mazda wouldn't warranty it, because they weren't running proper gas.

[Lockdown]

Explain the turbo and octane to me please.

Perhaps I am misunderstanding you but something doesn't compute here.

I would also like to know which Mazda dealer is telling people that they can ruin their TURBO from a lower octane.
I can see just about every other part of the system failing before that.

[Reddie1337]

Explain the turbo and octane to me please.

Perhaps I am misunderstanding you but something doesn't compute here.

I would also like to know which Mazda dealer is telling people that they can ruin their TURBO from a lower octane.
I can see just about every other part of the system failing before that.

We had a 2007 Mazda CX-7 traded in, with the 5 year, 100000km power train warranty still in effect. Around 87000km, the owner that purchased it from us, started complaining that the engine was really noisy, and it didn't have the power it should have. We couldn't figure anything out, and the oil was down about 1 litre. So we topped the oil up, and still had the noise. We sent it to Mazda, and they said that the VVT actuators had a part that wears out, and that makes the noise they were having. Now, this should have been covered under warranty, but the owner couldn't come up with any proof of oil changes, Mazda said the only way we might be able to fix it is if the engine appears to have been maintained properly. They took it apart, and it looked fine. They tested the fuel, and it was 87 octane. Mazda Canada decided they would not warranty this issue, after spending a fair bit of money to fix the actuator, it still didn't have it's regular power. At this point, it was determined the turbo was shot.

Wether the turbo was shot because of the actuator problem, or the fuel itself. I am not sure, but all I know is it cost over 4500 to fix it, and it seems to have stemmed from the owner not caring to run premium fuel.

[silverstarmazda]

not enough people read theyre owners manual wen they get a car and think all cars are the same

[Johns 08 3 GT]

Wether the turbo was shot because of the actuator problem, or the fuel itself. I am not sure, but all I know is it cost over 4500 to fix it, and it seems to have stemmed from the owner not caring to run premium fuel.

It sounds like the owner did not keep up on oil changes and thats why the VVT's failed. And IIRC the '07 is 91 octane but the '08 and later can run 87.

[Lockdown]

We had a 2007 Mazda CX-7 traded in, with the 5 year, 100000km power train warranty still in effect. Around 87000km, the owner that purchased it from us, started complaining that the engine was really noisy, and it didn't have the power it should have. We couldn't figure anything out, and the oil was down about 1 litre. So we topped the oil up, and still had the noise. We sent it to Mazda, and they said that the VVT actuators had a part that wears out, and that makes the noise they were having. Now, this should have been covered under warranty, but the owner couldn't come up with any proof of oil changes, Mazda said the only way we might be able to fix it is if the engine appears to have been maintained properly. They took it apart, and it looked fine. They tested the fuel, and it was 87 octane. Mazda Canada decided they would not warranty this issue, after spending a fair bit of money to fix the actuator, it still didn't have it's regular power. At this point, it was determined the turbo was shot.

Wether the turbo was shot because of the actuator problem, or the fuel itself. I am not sure, but all I know is it cost over 4500 to fix it, and it seems to have stemmed from the owner not caring to run premium fuel.

OK. So the turbo was shot because of an oil issue.
See now that makes sense.
I don't see how the octane level has anything to do with covering a turbo unless you are trying not to cover it and trying to build a case of character but that's pretty shady and you would need an awful lot more than that.

From the little information given, it appears as though the issues arose from poor maintenance. Would be nice to know where the oil went. Did it blow by, did it burn, was it not filled correctly on the previous change?
So many factors and possibilities but to do a full tear down and not be able to find out the root is an issue in itself.

As for the octane rating of the gas in the tank, how they tested it plays a bit in the results as well. I would be interested to know if they tested RON, MON or (R+M)/2 and how a test is performed. In all honesty, that is something I don't know. I am unsure how you can remove the fuel from a tank and then run the test and somehow factor in any and all particulates that could be present in a fuel tank. I'm sure its filtered in a similar manner to the way the vehicle does but setting up pressure regulations for a given series of filters seems like a task reserved for multimillion dollar law suits but maybe they have their own crazy labs. It could have simply been the first time the engine had ever seen that type of gas and if they are not looking for self ignition inside the combustion chamber, then that is a shit load of work for nothing. It could have been the mistake of a full service attendant, it wouldn't hold up.

It's just that there is so much misinformation on here and the Internet in general and a lot of people do not fully understand how an engine works, adding a turbocharger to it, just complicates things even more and then trying to explain what an octane rating is and how it can affect different aspects of the combustion process would be enough to confuse many who understand fluid dynamics and mechanical engineering. Those same people may go and tell their friends and so on and so on. This is how myths and incorrect information are spread. We should all try and think just a little that if we know something as fact or have heard it in passing.
I'm not sure what you do at the shop or dealership but I'm guessing we are reading what you can recall from one of the mechanics or the service advisor and a few pieces of key information were missing from the original post. Sorry for the long winded reply but I didn't want to come across as a dick but also had a few points to get out there and am genuinely curious on the testing. If you can find any information from the testers on how it is performed, I have only heard of testing from a source to test the validity of their claims, similar to how a lot of tests are performed on products at source or from purchased, sealed containers.

[Reddie1337]

Quite honestly, I am not sure how they came to the conclusion. This is what was told to me, after all this work needed to be done. And I genuinely have no idea as to how they tested it. All I know is this is what was presented as the reason, and I make damn sure every tank that is going in that CX-7 is premium now. It was a costly mistake (who is responsible, I'm not sure) all I know is that I wouldn't take a chance with a turbo in my life after seeing the cost of this repair. I am a strong believer in maintenance, and preventative maintenance. I check my car over every time before I do a long road trip. And anything I see as a problem I fix.

Honestly, I don't see you as a dick anyways. And you do have good points.

Back on topic though, I think their testing was flawed in the video. Draining the tank and refilling and running the test right after is not the proper way to go about it.

That's why I am now running premium in my car to see if it makes any difference at all, over a longer period of time. And for the cost difference, I will have to do an extra 65 km on this tank (averaging 10L/100km) to compensate spending more on the fill.

($8 extra cost on the fill with premium, would have added 6.5 L on to the amount of gas I would have gotten from just buying regular for the same amount of money.)

This is more of a test to see for myself if it does anything different, because of all the information thrown around on the internet.

[Lockdown]

I like that you are doing your own tests. First hand experience is great. That way you know what works for you. I 100% agree that the tests performed in the video, were not the way I would have done them. Sometimes the media sensationalize in a hunt for better ratings and in their search for better ratings, they may perform tests that will show results that are positive or compliment their way of thinking or their intended point.
They could have just as easily produced a study that says minty air fresheners increase the efficiency of air conditioners or that the tree outside of my house keeps tigers away.

I don't really know the specifics of the engines and computer of the Mazda 3 or the speed 3 enough to know what works and what doesn't yet, I'm still absorbing like a sponge.

Ask me about Spanish Oak and a 3V, maybe another story.

[Flagrum_3]

I like that you are doing your own tests. First hand experience is great. That way you know what works for you. I 100% agree that the tests performed in the video, were not the way I would have done them. Sometimes the media sensationalize in a hunt for better ratings and in their search for better ratings, they may perform tests that will show results that are positive or compliment their way of thinking or their intended point.
They could have just as easily produced a study that says minty air fresheners increase the efficiency of air conditioners or that the tree outside of my house keeps tigers away.

I don't really know the specifics of the engines and computer of the Mazda 3 or the speed 3 enough to know what works and what doesn't yet, I'm still absorbing like a sponge.

Ask me about Spanish Oak and a 3V, maybe another story.

I agree the tests could have been better, i.e; more 'intrusive', but as for showing whether using 'premium' in a 'regular' gas vehicle gives any benefits (i.e; more horsepower or better gas mileage), I think the tests are pretty conclusive!...It only takes moments with the proper equipment to show this, and I would say the numbers speak for themselfs. If one believes otherwise, then they can throw out all the HP/torque readings they have gotten or manufacturer claimed specs. It's pretty obvious using premium in a regular vehicle is useless, wasteful and 'possibly' detrimental to engine longevity, due to carbon build-up. A longevity test would require very long term study and the final dismantling of the engine to investigate the conditions of internal components.
I don't believe the computers in our cars can compensate in this 'particular' situation but they may be able too in the opposite condition, as in using regular in a premium car. As the compensation would only require adjusting the timing to prevent knock or pre-detination...Note; 'may' is the big word here. There is a reason 'premium' is recommended, and it is simply due to compression issues. A higher compression requires a higher ignition point and a slower burning fuel. There are many factures here to consider, including the head design. It may be actually possible to use regular gas in a 'recommended' premium engine, depending on internal design and obviously driving habits. It is quite possible one could 'granny' drive around a corvette, using only regular and never see any detrimental effects. But if one wants to 'push' thier vehicle then I'm sure there would be issues....I'm am talking 'stock' specs here with no horsepower increasing upgrades.... I certainly wouldn't drive a Z06 or ZR1 or a tricked-out Mazdaspeed3 using anything less then premium.


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