What grade of gas to use??
June-25th-2002, 10:37 AM
#31
Protege Enthusiast
Join Date: Jun 2002
Location: Bellevue, WA
Posts: 109
Okay. So I guess my question here now is, does the fuel computer map what kind of fuel I fill up with at the gas pump? When I called Mazda Customer Service the answer I got was 87 plus. How am I supposed to believe anyone these days. What's to say that the engine is really supposed to run on Mid-grade, but you can run it with regular and Mazda's marketing group says people like cheap gasoline. Let's tell them they can run crap gas in their cars so they think that they are saving money! I mean the Protege IS Mazda's entry-level (read: cheapest) car out there.
Now, one of the articles I read further up in the thread (internet link) talks about a guy saying that crap gas cost him valve work. Well, he had an imported car (an old volvo) and further down, the article says that the US has the crudest gas in the world octane-wise. Apparently lots of manufacturers de-tune their engines for US export because we simply don't run higher octane gas. Apparently Germany has 94 Octane at the pump! Our Premium to the Germans is 'Regular'.
Now, my question is, what octane ratings do they have in Japan? People with J-spec engines should be very careful with what they put in their engines. I believe that until I get a straight answer from someone, I will run 89 Octane. That seems to be the best compromise.
Now, one of the articles I read further up in the thread (internet link) talks about a guy saying that crap gas cost him valve work. Well, he had an imported car (an old volvo) and further down, the article says that the US has the crudest gas in the world octane-wise. Apparently lots of manufacturers de-tune their engines for US export because we simply don't run higher octane gas. Apparently Germany has 94 Octane at the pump! Our Premium to the Germans is 'Regular'.
Now, my question is, what octane ratings do they have in Japan? People with J-spec engines should be very careful with what they put in their engines. I believe that until I get a straight answer from someone, I will run 89 Octane. That seems to be the best compromise.
Last edited by zeriak; June-25th-2002 at 10:40 AM.
June-25th-2002, 11:27 AM
#32
Passion for Zoom Zoom!
Join Date: May 2002
Location: San Diego, CA
Posts: 372
I'm not quite sure why there is such opposition to using 87 octane fuel.
The manufacturer not only recommends, but specifically states using 87 octane fuel is best for your car's performance and longetivity.
The government, through agencies such as the National Highway Traffic and Safety Administration (NHTSA) and the Department of Transportation (DoT), state through many studies that using fuel with a higher octane rating than your engine is designed for is a waste of money and decreases fuel mileage.
Highly respected groups and associations such as the American Automobile Association (AAA) and the Canadian Automobile Association (CAA) state through many studies that using fuel with a higher octane rating than you engine is designed for is a waste of money and decreases fuel mileage.
Enthusiasts clubs (who are very worried about performance and reliability), such as the Miata Club of America (the largest single model car club in the world), recommends using the octane rating your car is designed for.
So who is it that recommends using high octane fuels all the time? The gasoline companies! Those who are charging $1.92 per gallon for 91 octane premium fuel...
So, if you still insist on using 89, 91, or 94 octane in your stock or lightly modified engine which has been specifically tuned and designed to run on 87 octane, then go ahead. If you don't mind higher costs, lower fuel economy, carbon deposits, and lower performance, then please use higher octane! Those of us who would like to properly care for our cars and avoid nasty repair bills will listen to the people who regulate, design, build, study, maintain, and repair our cars.
The manufacturer not only recommends, but specifically states using 87 octane fuel is best for your car's performance and longetivity.
The government, through agencies such as the National Highway Traffic and Safety Administration (NHTSA) and the Department of Transportation (DoT), state through many studies that using fuel with a higher octane rating than your engine is designed for is a waste of money and decreases fuel mileage.
Highly respected groups and associations such as the American Automobile Association (AAA) and the Canadian Automobile Association (CAA) state through many studies that using fuel with a higher octane rating than you engine is designed for is a waste of money and decreases fuel mileage.
Enthusiasts clubs (who are very worried about performance and reliability), such as the Miata Club of America (the largest single model car club in the world), recommends using the octane rating your car is designed for.
So who is it that recommends using high octane fuels all the time? The gasoline companies! Those who are charging $1.92 per gallon for 91 octane premium fuel...
So, if you still insist on using 89, 91, or 94 octane in your stock or lightly modified engine which has been specifically tuned and designed to run on 87 octane, then go ahead. If you don't mind higher costs, lower fuel economy, carbon deposits, and lower performance, then please use higher octane! Those of us who would like to properly care for our cars and avoid nasty repair bills will listen to the people who regulate, design, build, study, maintain, and repair our cars.
June-25th-2002, 12:37 PM
#33
Protege Enthusiast
Join Date: Jun 2002
Location: Bellevue, WA
Posts: 109
I guess I just wont be satisfied with what everyone is saying. I'll change my gas usage to 89 octane. In the book it says to use "at least" 87 octane.
Now I know my manual is different than everyone else's manual but I think we can all agree that it says "at least 87" or "87 or higher".
Okay, so I guess the only real test to see if the gasoline you put in your car is not designed to be in your car is to look at the spark plugs when you change them. I will try to keep my spark plugs when I change them since I have been running higher octane than 87 for most of the car's operation. I'll take digital pictures and post them sometime. Now I need to borrow the girlfriend's digital camera
"Your Mazda will perform best with regular unleaded fuel having an octane rating (antiknock index) of at least 87 [(R+M)/2 method]."
Okay, so I guess the only real test to see if the gasoline you put in your car is not designed to be in your car is to look at the spark plugs when you change them. I will try to keep my spark plugs when I change them since I have been running higher octane than 87 for most of the car's operation. I'll take digital pictures and post them sometime. Now I need to borrow the girlfriend's digital camera
June-25th-2002, 01:49 PM
#34
Protege Enthusiast
Join Date: Jan 2002
Location: Atlanta, Georgia
Posts: 154
one reason that i worry about using 87 octane (although i have always used it) is that gas stations have worse gas than others. meaning that, for some reason or another (its a long explanation), the fuel does not have the octane rating that they advertise. this can cause big problems.
June-25th-2002, 03:55 PM
#35
Protege Enthusiast
Join Date: Oct 2001
Location: Regina, Canada
Posts: 307
I have a family member who works in Alberta with the gas business. It turns out that in Canada, all gas stations get their fuel from one of 2 or 3 companies. So it's really all the same gas regardsless of where you go. SOme companies may add things to the gas once they buy it but it's still your basic 87, 89 or 91 octane fuel. Those who want to believe otherwise can do so it their own expense.
As for this over-discussed octane matter. Obviously these people enter this thread wanting to read that our simple economy cars need high octane fuel. They can, and do, read through dozens of posts containing facts and proof regarding the ill effects of using higher octane fuel than you car is tuned for. These people are looking for the opinion of one or two individuals who for some reason think 89 or 91 octane may be better, and grasp to that idea like a life preserver. IMO, it's not much different than silly ricers who want to believe that their pointless mods(spoilers, coffee cans, cutting springs) will actually add performance to their cars. These people will wade through wave after wave of proof that these things hinder more than hurt just to latch onto someone's "first hand experience" where they claim that cutting springs gave them better handling.
Whatever..., it's your money to waste and your car to damage.
"Ignorance is bliss"
As for this over-discussed octane matter. Obviously these people enter this thread wanting to read that our simple economy cars need high octane fuel. They can, and do, read through dozens of posts containing facts and proof regarding the ill effects of using higher octane fuel than you car is tuned for. These people are looking for the opinion of one or two individuals who for some reason think 89 or 91 octane may be better, and grasp to that idea like a life preserver. IMO, it's not much different than silly ricers who want to believe that their pointless mods(spoilers, coffee cans, cutting springs) will actually add performance to their cars. These people will wade through wave after wave of proof that these things hinder more than hurt just to latch onto someone's "first hand experience" where they claim that cutting springs gave them better handling.
Whatever..., it's your money to waste and your car to damage."Ignorance is bliss"
June-25th-2002, 04:26 PM
#37
Registered User
Join Date: Jun 2002
Location: Maryland
Posts: 38
My protege is on it's 4th tank of gas right now.
I'm not sure what the dealer put in as the first tank, but I filled it with premium for the first 2 fillups.
On my 3rd fill up (the 4th tank), i tried putting in regular gas. I listened VERY carefully for any difference in "smoothness", and I detected nothing. Engine temps were also the same. $2 a tank adds up over time. I'll be using 87 octane from now on, unless I ever up my compression ratio or something, which is unlikely.
My dad takes excellent care of his cars, always uses the gas they are designed for, and none have ever had any problems. He also does not use those fuel additives.
A friend of mine had a tercel that ran to 260k miles, his family ran regular gas in it the entire time. Even at 260k miles, it sounded just like a new engine.
I'm not sure what the dealer put in as the first tank, but I filled it with premium for the first 2 fillups.
On my 3rd fill up (the 4th tank), i tried putting in regular gas. I listened VERY carefully for any difference in "smoothness", and I detected nothing. Engine temps were also the same. $2 a tank adds up over time. I'll be using 87 octane from now on, unless I ever up my compression ratio or something, which is unlikely.
My dad takes excellent care of his cars, always uses the gas they are designed for, and none have ever had any problems. He also does not use those fuel additives.
A friend of mine had a tercel that ran to 260k miles, his family ran regular gas in it the entire time. Even at 260k miles, it sounded just like a new engine.
June-25th-2002, 04:37 PM
#38
Protege Enthusiast
Join Date: Jun 2002
Location: Bellevue, WA
Posts: 109
Well, I'm going to jump this thread because it just sparked into flame.
My POV is:
Manual says 87 octane "at least" or "or higher".
Foreign cars use higher octane fuel. Protege is an imported car.
ECU is tuned for 87 octane. How does anyone know? Did someone here program the ECU for the Protege? Does the ECU adapt to the fuel given? No one knows for sure. Post an email from a Mazda engineer or Mazda's engineering tests before you start flaming everyone who doesn't agree with your notion of which gas to use.
I personally called the Customer Service center where the CSR asked the "tech guy" what fuel to use. She replied with "87 plus". Now, this sounds kind of hokey, who is this "tech guy" anyway?
It all boils down to this. The manual and the specifications of the engine itself says to use "87 plus". The MP3 motor which if I am correct is essentially a 2.0L with a different cams is recommended 91 octane.
The choice is yours. Now that I have done a little research on the matter, I will go with 89 Octane to be safe. One step above 87 one step below 91. Sounds like a happy compromise to me. I may run some of that redline stuff in my car every once in a while anyways. Other than that, it's not like using 89 or higher Octane is like pouring diesel into the gas tank.
My POV is:
Manual says 87 octane "at least" or "or higher".
Foreign cars use higher octane fuel. Protege is an imported car.
ECU is tuned for 87 octane. How does anyone know? Did someone here program the ECU for the Protege? Does the ECU adapt to the fuel given? No one knows for sure. Post an email from a Mazda engineer or Mazda's engineering tests before you start flaming everyone who doesn't agree with your notion of which gas to use.
I personally called the Customer Service center where the CSR asked the "tech guy" what fuel to use. She replied with "87 plus". Now, this sounds kind of hokey, who is this "tech guy" anyway?
It all boils down to this. The manual and the specifications of the engine itself says to use "87 plus". The MP3 motor which if I am correct is essentially a 2.0L with a different cams is recommended 91 octane.
The choice is yours. Now that I have done a little research on the matter, I will go with 89 Octane to be safe. One step above 87 one step below 91. Sounds like a happy compromise to me. I may run some of that redline stuff in my car every once in a while anyways. Other than that, it's not like using 89 or higher Octane is like pouring diesel into the gas tank.
June-25th-2002, 05:13 PM
#39
Passion for Zoom Zoom!
Join Date: May 2002
Location: San Diego, CA
Posts: 372
The MP3 gets part of its increased horsepower because the ECU is programmed for premium fuel. The MP3 does have a knock sensor and lower octane can be used. However, the engine will produce less power because the ECU is retarding the timing.
However, it is not the other way around. The standard ECUs will not advance ignition timing to take advantage of premium fuel. We've had this discussion about a year ago on the Edmunds board where a Mazda employee is a regular. He checked with the engineers about that...
The Protege is indeed a foreign car. However, foreign cars are designed to run on higher octane gasoline when they are sold in foreign countries. This is why, in general, our car's European and Asian versions put out more power from the same engine. Like it was said in a previous link, most foreign vehicles are drastically detuned for our crappy fuel.
But, use whatever you like. Except for the few months I believed the hype about higher octane, I've been running 87 octane in my Protege for over 3.5 years now and I have yet to hear single knock or ping.
-Jerry
However, it is not the other way around. The standard ECUs will not advance ignition timing to take advantage of premium fuel. We've had this discussion about a year ago on the Edmunds board where a Mazda employee is a regular. He checked with the engineers about that...
The Protege is indeed a foreign car. However, foreign cars are designed to run on higher octane gasoline when they are sold in foreign countries. This is why, in general, our car's European and Asian versions put out more power from the same engine. Like it was said in a previous link, most foreign vehicles are drastically detuned for our crappy fuel.
But, use whatever you like. Except for the few months I believed the hype about higher octane, I've been running 87 octane in my Protege for over 3.5 years now and I have yet to hear single knock or ping.
-Jerry
June-25th-2002, 05:34 PM
#40
Show Layne some respect
Join Date: Nov 2001
Location: Long Island,NY
Posts: 2,458
Originally posted by zeriak
Now that I have done a little research on the matter, I will go with 89 Octane to be safe.
Now that I have done a little research on the matter, I will go with 89 Octane to be safe.
What no one here wants to admit is the psychology of this whole discussion. There is no benefit to using 89 octane in a relatively low-compression engine that is designed for 87 octane. For crying out loud - the difference between 87 and 89 is nearly negligible anyway. The only benefit is the "warm and fuzzy" feeling you get from "treating your Protege right" - after all, more expensive always equals better, right?
The same conflict exists with spark plugs - people think that using plugs with "more spark" will give "more power", and this is utterly false. I have first hand experience. I decided to run SplitFire plugs in my Miata a few years ago. I thought I was feeling a power difference, too. Then, about two weeks later, the engine starts pinging and hesitating. I changed to premium fuel, which helped for about 1 tank - then the pinging was back. So I changed plugs again, thinking maybe the "crappy" 87 gas fouled up my plugs. This time, about two days go by, and the pinging is back. I ask a mechanic I respect, who tells me that the plugs are too hot for the engine. The excess heat they generate is causing detonation - fuel igniting beore the spark, due to compression - like a deisel motor. And the extra octane gas wasn't helping.
When I pulled the second set of plugs, the carbon build-up was extroadinary - one week of use, and I had plugs that looked like they had 100,000 miles on them.
I switched back to the OEM spec plugs, and 87 octane. The car ran flawlessly from that point on.
June-25th-2002, 05:44 PM
#41
Protege Enthusiast
Join Date: Jun 2002
Location: Bellevue, WA
Posts: 109
Hehe the warm fuzzies is worth the extra 5 cents a gallon. I will check my plugs tonight. If it don't hurt, why is everyone getting so heated about me using 89 or even 91? If the difference isn't that great anyways what does it hurt?
I know what it is... Ok, Ok, you guys are all right about the 87 octane thing. I am so wrong. So so very wrong, I have never been so wrong about anything since I told people that "Pat" from SNL is really a woman...
You guys happy now? Everyone run 87 oct in your Protege, I'm going to run 89 anyways. If anything, just to **** you guys off. J/K
I know what it is... Ok, Ok, you guys are all right about the 87 octane thing. I am so wrong. So so very wrong, I have never been so wrong about anything since I told people that "Pat" from SNL is really a woman...
You guys happy now? Everyone run 87 oct in your Protege, I'm going to run 89 anyways. If anything, just to **** you guys off. J/K
June-26th-2002, 11:05 AM
#43
Protege Enthusiast
Join Date: May 2002
Posts: 140
Octane ratings and what to run is very simple.
First find out your exact compression ratio. 8.1 to 9.4 you should use 87 octane. for 9.5 to 10. 89 octane is what you should be running. For an engine with 10.1 or higher, you should run 91 or higher.
Compression ratio determines exactly what octane you should run. The higher the ratio the hotter the engine the more octane you need to cool it down.
Now if you don't know 87 octane burns the hottest and the fastest. 91 and up octane is a more slow controlled burn.
Higher compression engines ignite the fuel before its comes to the TDC of the compression stroke, hence the need for the higher octane fuel, to elimiante preignition.
First find out your exact compression ratio. 8.1 to 9.4 you should use 87 octane. for 9.5 to 10. 89 octane is what you should be running. For an engine with 10.1 or higher, you should run 91 or higher.
Compression ratio determines exactly what octane you should run. The higher the ratio the hotter the engine the more octane you need to cool it down.
Now if you don't know 87 octane burns the hottest and the fastest. 91 and up octane is a more slow controlled burn.
Higher compression engines ignite the fuel before its comes to the TDC of the compression stroke, hence the need for the higher octane fuel, to elimiante preignition.
June-26th-2002, 12:02 PM
#44
Passion for Zoom Zoom!
Join Date: May 2002
Location: San Diego, CA
Posts: 372
3rd Generation Mazda Protege Compression Ratios
1.6L ZM-DE... 9.0:1
1.8L FP-DE... 9.1:1
2.0L FS-DE... 9.1:1
2.0L FS-DE... 9.1:1 (MP3)
And just because there are some people running these engines (who should use high octane!):
2.0L FS-ZE... 10.5:1
1.6L ZM-DE... 9.0:1
1.8L FP-DE... 9.1:1
2.0L FS-DE... 9.1:1
2.0L FS-DE... 9.1:1 (MP3)
And just because there are some people running these engines (who should use high octane!):
2.0L FS-ZE... 10.5:1