Regular Gas for 2008 CX7

chillum

Member
I read in the car and driver or road and track SUV review for 2008 that the 2008 cx7 now has premium fuel 'recomended' rather than required after a computer 'update'. Is that true and can we get that for a 2007 CX7?

Also if we ask for the latest flash does that include all the previous updates?

What should I ask for? ECM, TCB? All the terms are confusing..

Thanks for the help!
 
91 Octane fuel is still the recommended fuel for the 2008 MY. Using less than 91 octane will cause lower performance, possibly poor shift quality and reduced provability. If you can't afford to put the recommended fuel in the car I'd recommend buying a car that recommends 89 or 87 octane fuel. The TSBs are for the TCM & the ECM. Are you having issues with your transmission or engine? If not, then why brother with the TSBs? In addition: the TSBs are related to the build date & VIN #.
 
I am having hesitation off the line and the 5/6 gear shift issues. I did confirm that my car falls in the VIN range and build date.

I also have been averaging about 13.5 miles over the first 3500 miles with mainly city driving 85%. I was hoping they made an adjustment on the fuel requirements where it would not change performance.

In Miami the difference can be upto 40 cents per gallon. I was just curious if we still needed to put premium in it based on the article i read.

I realize I can always get a new car, its not an affordability issue. That line of 'buy another car' is overused when discussing this topic it seems. Why does that have to always be the only response? Rich people don't buy $25,000 Mazdas.

But thanks for the help.
 
Go to the Mazda owners web site and look at your owners manual. The section that comments on fuel octane lists some of the issues you will/may experience if you choose a lower than recommended fuel. People in AK run their CX7s on the highest octane fuel available which is 90 octane. I would never ever run less than 89 except in a real emergency. Didn't mean to be condescending with my comment about getting a vehicle you can afford to run. Just seems foolish to buy a vehicle, knowing what the required or recommended fuel is and then have issues with an extra $3 per fill up. I too grit my teeth at the gas companies prices and in my case, I choose to curtail my driving mileage and use the 91 recommended. JMW. Ed
 
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I was just hoping that it was no longer a requirement. The problem I have is that the salesman told me 'off the record' it was just a reccomendation and that you could run regular. Then I a couple days after taking delivery I find out that it is a requirement and that if you use anything else it may void the warranty! So I guess my displeasure stems from that. I agree that over all with my low annual mileage (3500 miles in 7+ months) its not a big deal. I was just wonderingif anyone had any more info than the blurb I read. Hell we pay over 5$/gallon for bottled water and oer 8$/gallon for starbucks so whats an extra 40cents right!
 
A friend of mine who works at the dealership we bought out 2007 CX7 from last July said their GM has a 2007 CX7 and has run it with nothing but 87 for almost a year.

He bragged about it enough that I would guess their salesmen might use that pitch if someone balks at the premium fuel required/recommended label for the CX7.

I'm not condoning it or saying that it doesn't run like crap. These are the kind of statements that are coming out of Mazda's sales side though.

I've never tried anything less than 91. At our altitude I could probably get away with 89, but I wouldn't try 87. But in reality, the cost savings from 91 to 89 are <2 bucks. So its not that big of a deal. Now if we could get off the winter mix and raise my 15mpg in the winter....
 
This is exactly why I didn't get the CX7. I was getting rid of a car that required premium so I wasn't about to get another one that requires it too. Gas is expensive enough as it is and I don't need to pay an additional $.30/gallon.
 
The sales side of the dealership has an agenda-TO SELL CARS-PERIOD. Not saying they always lie but, it is my money so I do my homework before consulting a dealer. I am averaging 21.57 mpg with my 07. I use 91 or higher as some of my staions premium is 93. When I get 93 I will fill with 89 when down to ~ 1/2 tank. JMW Ed I enjoy my vehicle very much and bought knowing 91 was required and expecting to get the EPA rating as I always have in the past. I am exceding the EPA new estiments and could have easly bought a vehicle that uses 87 octane but only got 16 mpg so performance wise & mileage I am $$ ahead.
 
It is only costing me an extra $208 annualy to burn 91 octane over 87 octane. I am averaging about 16,000 miles a year. Why bother with the cheap stuff. Keep the 91 octane in it. Performance Man! ZOOM ZOOM
 
No one has answered the simple question OP asked: whether a shop or a dealer can tune the 2007 engine to make it same as the 2008? It's a simple technical question. Can someone who knows just answer it without all the judgemental stuff?
 
I have read second hand that Mazda stated that there were engine modifications in addition to modifying the ECM software. The 2008 option can't be made retroactive to 2007. I do not remember the manual saying that 87 octane was OK, but that 91 was now recommended rather than required. Mazda has stated that the lastest software updates include ALL previous updates so if you get the ECM & TCM updates you will have it all. TMC=transmission control module and ECM=engine control module. Good kleung?
 
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chillum,

I have run 87, 89, 90, 91 and 93 octane in my 2007 CX-7 (built June 06) and this is what I've seen:

1- Under heavy and repeated WOT runs, I did not notice any knocking/pingin using the lower octane fuels; even in the hottest summer months.

2- Under heavy and repeated WOT, there was a very subtle hesitation, as if the engine had hit the rev limiter. I theorize the computer saw something it didn't like and either closed/open the throttle repeatedly and/or took/added timing and/or fuel. This doesn't necessarily mean the computer detected imminent destruction.....just something it didn't like.

3- Transmission shifting was not affected at all.....at least that I could sense.

4- Fuel mileage was mixed! It seems during the summer months, the higher octane got better MPGs. During the cold months, the lower octane seemed to have done better at times. At times, no matter what fuel I used and what time if the year it was, I got just about the same.
Now, Miami is my hometown, and if you haven't experienced cold other than Miami's, then you don't know what cold is. I'm now living in Missouri, where is much colder than the coldest day in Miami. Running a lower octane in the cold months in Miami might not have the same effect as in Missouri.

5- If maximum performance is desired, I do suggest running 93 octane. For normal and moderate driving, 87 or 89 did just fine.


I caught a lot of heat for doing this and reporting my findings here; so I'm risking going through it all over again.

Rick
 
I don't even bother to find out what the lower octane gas can do to my "new addiction"....she is fed prime/premium/ultimate/exceptional GAS. The difference in savings won't make me buy a mansion. If I'm stingy about money I would just have bought a Kia Rondo or a Chevy Aveo.

JUST ENJOY THE "Zoom-Zoom" while getting stares from the Interstate audience. Live it...love it.
 
Interesting observations Rick's CX7: I would have expected that the lower octane fuel ( 87) would show prononced performance degrdation at WOT but, much less at easy driving. I have two questions Rick. 1. did you run 2 or more tank fulls of the same octane one after another for your test? or did you go from 91/93 to 87 so you got a mix? 2. Did you find a difference in the brand of fuel used i.e. Shell/Chevron/BP etc. vs no name?
 
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To echo what was said above, there is more than a PCM program to make the 08's run on regular, there were some mechanical changes as well. So the changes can't be made to the 07 without great expense.
 
Ed,

I ran numerous tanks of 87 and 89 consecutively for hundreds of miles, without interruption. Again, never experience any knocking/pingin.....just that hesitation I mentioned under heavy WOT, where the ECM seemed to have slightly closed the throttle. This did NOT happen all the time either.
Interestingly, the only time EVER that I've got pinging was just 3 days ago, running 93 Mobil gas. I stepped on the gas from a 25-30mph roll and the engine pinged, then bucked and then took off normally. The tranny was in auto mode. First time this engine has hiccuped liked this.

Rick
 
Ed,

I ran numerous tanks of 87 and 89 consecutively for hundreds of miles, without interruption. Again, never experience any knocking/pingin.....just that hesitation I mentioned under heavy WOT, where the ECM seemed to have slightly closed the throttle. This did NOT happen all the time either.
Interestingly, the only time EVER that I've got pinging was just 3 days ago, running 93 Mobil gas. I stepped on the gas from a 25-30mph roll and the engine pinged, then bucked and then took off normally. The tranny was in auto mode. First time this engine has hiccuped liked this.

Rick
Makes me wonder why the insistance of Mazda with the 91 min. requirement on the 07. Could there be an issue with carbon build up over time or some other issue I can figure out? I may try a tank of 89 and see if my 07 does ok. I know they sell AK CX7s that run on 90 as that is the best availiable. Ed in SW FL.
 
I should also mention that I have been running 93 since 3 months ago. I've decided to stick with it for the time being. I may run 87/89 again without hesitation though.

I would encourage other people to try 89 and report back to us. One car is just not enough data to prove/disprove anything!
 
Running my 07 on a top tier 89 octane Shell fuel now. I suspect that problems will be magnified when using a heavy throttle in manual mode. The AT is more forgiving by not being able to lug the engine or even load too heavy without downshifting. presently I'm driving normal i.e. 20000--3000rpm shifts using the AT. Will report after 3 tank fulls (325 miles/tank) or less if issues arise. Ed
 
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