Premium or Regular Gas?

Find out who the jobbers are for the independents in your area. It may be that they're getting good gas. You never know until you find out who their suppliers (jobbers) are. If my terminology is off, the concept isn't).
 
so something like you can save about 10% onthe cost of fuel but it is going to cost you 30% of the mpg you get in my case 23mpg down to 16 mpg not to mention a 30% power loss to. It seem like I going to put the 91 octane in.
 
Blending 91 octane

Although the dealership said that you could run 2 tanks of mid after every 1 tank of premium, I'm not so keen on the idea - at least until I have a much more intimate familiarity with the performance of the engine.

Keep in mind that our CX-7 is not an everyday car... so I'm not at the gas pumps every other day, but I have been using a 50/50 mix of the mid 89, and the premium 93 when I fill up. The blending not only creates the recommended 91 octane, but also saves a little money - about a buc or so, but its someting.

I've got about 1000 miles so far... I have been flexing rpms into the 5000 - 6300 range periodically during the break-in, and I have not experienced any detonation, or other quirks. I continue to be amazed at the performance of this vehicle. Its a 4 cylinder that drives like a V8 - no matter where you are, all you need to do is touch the pedal a little to access everything it keeps in reserve.

First two fill-ups, and I have gotten 18.9 and 19.4 mpg - and that is not by driving efficiently.
 
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More info on "top tier" gas from about.com (yes, more info about the retailers than just the pathetic list on the official site:
about.com said:
Chevron: Chevron has markets in 29 states in the West, Southwest and South, as well as in Alaska and Hawaii. ALL grades of Chevron with Techron gasoline meet TOP TIER Detergent Gasoline Standards. QuikTrip: (Not to be confused with Kwik Trip). QuikTrip operates convenience stores and travel centers in a number of metropolitan areas:
  • Tulsa, OK
  • Springfield, MO
  • Kansas City, MO
  • Kansas City, KS
  • Wichita, KS
  • Des Moines, IA
  • Omaha, NE
  • St. Louis, MO
  • St. Louis, IL
  • Atlanta, GA
  • Dallas-Ft. Worth, TX
  • Phoenix, AZ
  • Bartlesville, OK
  • Miami, OK
  • Vinita, OK
  • Columbia, MO
Kwik Trip: (Not to be confused with QuikTrip). Over 450 Kwik Trip, Kwik Star, Hearty Platter and Tobacco Outlet Plus stores throughout Wisconsin, Minnesota and Iowa.
Conoco: Conoco has over 4,000 stations located in 33 states.
Phillips 66: Phillips 66 has locations in 32 states across the nation.
76: 76 has over 2,700 stations located throughout the country.
Shell: Shell Oil Products has a network of nearly 7,000 branded gasoline stations in the Western United States. Shell Oil Company markets branded products through more than 10,000 stations in the Eastern and Southern United States.
Entec: Entec Stations offer gasoline through stations located in the greater Montgomery, Alabama area.
MFA: MFA Oil Company offers gasoline at "Break Time" convenience stores located throughout Missouri.

Anyone else notice that not a single entry on this list is in the Northeast??? :bs::bs:

ARGHARGH. It sucks though because I know shell is in the northeast (I've seen one.. just one.. in CT before) but their store locater web site (www.localshell.com) is down currently.
 
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I have used 90 rated 90% gas/10% ethanol mix once (see my thread from a month ago). I had no problems whatsoever.
 
Need a quick answer here. Bought a cx7 yesterday from a dealer 200 miles away. They are to deliver it to me next week. This is my first Foreign car or turbocharged. I didn't even think of it having to use premium gas. Not a mention of it from the salesman (pissed) Got home and started research, and figured out it needs premium. My problem is the highest octane offered for at least 60 miles is an ethanol blend with an 89 octane. Called the salesman about my problem, he didn't believe me and starting calling all the stations. Finally he agreed. Here is my problem, I'm into the contract but will be unable to put 91+ in the car except in rare case while traveling. Has any one ran the 89 octane, and what happens? Is fuel additives an option? . I really wanted the car, should I try to see how it runs on that fuel or try to negotiate out of my contract. Already have Mazda financing, so I may be stuck with a different kind of Mazda I don't want. HELP
 
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It NEEDS 91+ octane Bas... Not only will you potentially has misfire problems with lower, but the dealer could void your warranty.
 
basunnyday said:
Need a quick answer here. Bought a cx7 yesterday from a dealer 200 miles away. They are to deliver it to me next week. This is my first Foreign car or turbocharged. I didn't even think of it having to use premium gas. Not a mention of it from the salesman (pissed) Got home and started research, and figured out it needs premium. My problem is the highest octane offered for at least 60 miles is an ethanol blend with an 89 octane. Called the salesman about my problem, he didn't believe me and starting calling all the stations. Finally he agreed. Here is my problem, I'm into the contract but will be unable to put 91+ in the car except in rare case while traveling. Has any one ran the 89 octane, and what happens? Is fuel additives an option? . I really wanted the car, should I try to see how it runs on that fuel or try to negotiate out of my contract. Already have Mazda financing, so I may be stuck with a different kind of Mazda I don't want. HELP
Doesn't it ping with 89? I would not run 89 in that car.
 
Dim said:
Doesn't it ping with 89? I would not run 89 in that car.

I don't have the car yet. They are suppose to deliver it this week to me. So I don't know that was my question. Referring to the warranty. Using a lower octane will not void the warranty. I checked that out.
 
I found myself in a similar situation. I learned after my purchase that the best premium fuel offered in Alaska is 90. I assume that the car would perform better with 91, but it seems to be doing fine with the 90. My dealer assured me it should be fine. I don't know if droppping down another notch would make a significant difference.

I'll leave that to others who know more to answer.

I'm glad you confirmed that you won't have warrantee issues if you are stuck using 89 most of the time.
 
The question of minimum octane requirement should go to the Mazda factory and NOT to a service writer or self appointed expert.
 
heres teh thing. If when you get your car delivered and u fill up with lower than 91 octane rating, anything that happens as a result, in terms of service you will most definately need, MAzda does not recognize this as warranty service. Everytime your car (and it will) misfire, not run properly, have detonation with the strong possibility of the car's computer shutting off the car to protect the engine, you will be paying thru the nose for service due to the lack of required gasonline.

if the situation you are talking about is in fact true, the inability to put in the required rating of gas, you should not take delivery of this car and/or swap it out for another vehicle. its not a question of if you'll have problems, its just a matter of when.
 
and dont take this the wrong way, but given the specs on the Mazda and the fact that its turbo car, let alone suv, u should have been a little more inquisitive as to what grade of gas goes in it. Not only that, this def should have popped up in your research BEFORE you bought the car.
 
I'm sorry but, Mazda should not sell vehicles that require 91 octane gas where there is none. I said before, contact Mazda for the answer to the question as to whether 91 is mandatory or not. Hearsay and service writers may not be your best sourse of information. Do this BEFORE you take deleivery. JMO Ed
 
erhayes said:
I'm sorry but, Mazda should not sell vehicles that require 91 octane gas where there is none. I said before, contact Mazda for the answer to the question as to whether 91 is mandatory or not. Hearsay and service writers may not be your best sourse of information. Do this BEFORE you take deleivery. JMO Ed

Thank you for being understanding. I doubt if I will take delivery,(unless Mazda tells me it will be fine) and hope that the dealership does not make a big fuss out of it. The salesman knew that I lived in a rural area. Heck they were delivering it to me. Never a mention on the premium gas in a four hour period during negotiations. I live in Nebraska, now I have researched the premium gas thing well. It is nearly impossible to get it except along I-80. That leaves a lot of Nebraska being many miles away from premium. Kansas and Eastern Colorado have the same issues in rural areas. I plan on talking to Mazda before making a final decision. All I know is that I can't drive a 120 round trip to fuel up.

As for the post before, saying that I should have did my research. I have been shopping for several months, but only briefly looked at the Mazda site. I looked at the specifications, it does not have anything on it about premium gas. The brochure would not download.

I accidently found the Mazda, liked the styling, took a drive, liked it, worked out what I considered a fair deal. Picked out a loaded GT model with all the option except the navigation package, at $3,000-$9,000 lower than comparable cars. Why would I even consider that it would require special gas, I think the power of the engine is very comparable to the V-6 edge. None of the other comparables require premium. The fact that it has a turbo may mean something some of you, the fact is the horsepower is similar to the others. What sold me is the looks, the handling, and the price. I didn't think I was looking at a Porsche or a Jag but a stylish 4 door wagon, really not even an SUV.

I really liked the car and hope next year they offer the V6 that they use in the edge and CX9 as an option.
 
I bought my CX-7 dec 29 and drive about 5000 miles a month. The first month and a half i used 93 octane. About a month ago I switched to 87 and have been using it for the past 4000+ miles. I have had no issues except maybe a slight decrease in power. I saved $60 over the past month in gas by using 87 oct. I fill up at least every other day. As far as gas mileage i have not noticed a difference. I get 16-18 MPG regardless of the oct of fuel i use. I am going to switch back to 93 for the next few weeks and see if i notice any difference in power or MPG since the temperature is finally warming up a bit, live near Pittsburgh. I anticipate a slight power increase with no better MPG but want to give it a try since the engine should be broken in now, just hit 10,000 miles. But as far as having any problems with 87... I have had none
 

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