And the additive mixture might be added just before delivering to the station across the street! I've heard it's in the form of a solid brick...

 

If you are going to use cheap gas I would try to make it at Costco or Sams because the cheapo stations don't sell a lot of premium (91 or 93) so it sits in the tank for a long time. they also don't maintain there tanks well. E10 has a relatively short shelf life and a very high propensity to absorb water and to seperate into layers. You will get less detergent at Costco but at least you will get fresh gas and quality storage tanks.

 

No.....read the post above

 

I had to stop and go read about direct fuel injection. Did not realize it did involve going directly to the combustion chamber as opposed to just behind the intake valve. And I'm quite a motorhead, too.

There are a couple of reasons that bad gas can occasionally cause an issue. The primary one, as previously stated in replies here, is water. Most modern gas stations have fiberglass tanks underground. Steel ones were done away with long ago. Not sure if they tanks are unable to withstand the pressures of being below the earth. Another potential problem is the person checking the fuel level (for stations that don't have level sensors in them). He or she should CAREFULLY put the measuring stick into the tank to read the fuel level. I've heard stories of some employees just dropping the stick into the tank.

We have an oil refinery just up the way. ALL local stations get their gas there. If you drive by it, there are about 12 large tanks outside. Each one is for a specific gas station (at least the major brands; not sure about the mom-and-pop stores). Each company has its own unique formula that combines gas, ethanol, detergents, other additives, etc. Each tanker pulls up to a kiosk, punches in a code, and connects their hoses. Gas from one of the tanks pumps into his or her tanker truck. Also, remember there are winter and summer formulas set forth by the federal government.

My specific issue with bad gas was with cold starts. They occured for about two to three months. First attempt to start up, sputter. Second attempt, fired right up. After discussing on our local board, I realized I had been hitting Hess gas stations during that time. I quit going to them; cold start issue went away.

Interestingly, gasoline itself is a cleaner. Motorheads know you can soak an entire carburetor in a bucket of has to help clean it up before rebuilding it. However, combined with all the other chemicals, it's not going to be 100% clean. Think of it in terms of discolorization. Two clean alcohols out there are Vodka and moonshine. Vodka produces the least overhang compared to other liquors for that reason.

My father taught me a long time ago to use an STP fuel treatment about once every 3,000 miles. I don't consider it a necessity so much as peace of mind. I bought my '06 MCS in December. Mileage has been ho-hum at about 26 MPG in city. I was getting 28-30 MPG with my old '02 MCS. I ran through an STP fuel injection cleaner (black plastic bottle) a couple of weeks ago. I did notice a slight improvement in response and fuel consumption. My conclusion was we had a colder winter than previous. But, I will continue to use STP fuel treatments at 3,000-mile intervals or so (red plastic bottle).

As with what other posts say, it's not necessarily bad gas. But don't cast it out completely.

 

Turkey Hill Minit Market????

Ok, well, uh................

 

Until they put a stipulation in the manual that our MINIs require top tier gas I'm going to continue putting 93 octane gas from my 2 stations of choice - Hess and a local boy that has ethanol free gas.

That said I am going to do the seafoam treatment or run an additive through my tank soon as I definitely can feel that my engine isn't running as smoothly as it used to.

 

No worries... that would be shot down immediately by Mini's all-important Marketing Department -- Minis are becoming much harder to sell as it is.

Plus, it would be utterly unenforceable!

 

I read the Owner's manual and it only says not to use anything under 89 although 91 is preferred. So check your manual and see if it says the same as mine and ask them why would the manufacturer print that if it's not accurate.

 

Good thread...I have mostly only used Chevron gas, about 95% of the time I've had Steeler. The SA told me to use Chevron because of the techron.

Currently I have 67K miles and on occaision(started about 58K miles) I get an engine power loss cel (the yellow one that lights up in the tach display that's half filled in) which feels like the car is misfiring. I turn the car off, start it back up and no light. This has happened to me about 4 times.

Initially I thought, "well, I have to change out the spark plugs". I did this and have done several seafoam treatments. Last week, the same thing happened to me. Up until reading this thread I thought I had done something to the computer connectors because of having the pnp unichip. I had removed the unichip at about 25K miles and never used it again.

Now I'm thinking that maybe I have some of the "gunk" or something. How much is it to take to the dealership to get a good cleaning?

 

My SA advised me to use top tier gas. I was told that premium wasn't necessary... but my car runs differently on cheap gas. I hate when they top Viola up for me at the dealership because I can tell when they've put regular in it.

I've only ever fueled her with Shell V-Power.

 

FYI- The owners manual does recommend top tier but it's not required.

Quote from '09 online Clubman manual page 95.
Emphasis added:

"Use high-quality brands
Field experience has indicated significant differences
in fuel quality: volatility, composition,
additives, etc., among gasolines offered for sale
in the United States and Canada. Fuels containing
up to and including 10% ethanol or other
oxygenates with up to 2.8% oxygen by weight,
that is, 15% MTBE or 3% methanol plus an
equivalent amount of co-solvent, will not void
the applicable warranties with respect to defects
in materials or workmanship.
The use of poor-quality fuels may result in
driveability, starting and stalling problems
especially under certain environmental conditions
such as high ambient temperature and
high altitude.
Should you encounter driveability problems
which you suspect could be related to the fuel
you are using, we recommend that you respond
by switching to a recognized high-quality brand
such as gasoline that is advertised as Top Tier
Detergent Gasoline.
Failure to comply with these recommendations
may also result in unscheduled maintenance."

 

It doesn't exclusively recommend top tier gasoline. It recommends using any recognized high-quality brand. Top tier is simply an example.

 

Overall, it seems the lesson to be learned here is to avoid DI gasoline engines at all costs!

 

So the short post is - No "Top Tier Gas" in my area, so now what?! And +1/thumbs up for Techron. (I ramble below)

Have read through the thread, as I was checking up on posts regarding idle, cold start issues, etc. The misses' '07 MCS is about to crest 50K (and thus no more warranty), so I wanted to get some items to take to the dealer before we have to start paying for them out of pocket (much like regular service).

The fuel discussion is interesting, and I just wanted to add a comment about the "Top Tier Gas" list given earlier. What do we do if there are no "Top Tier Gas" stations in our area (Western New York)?! My hope is that Sunoco Canada would qualify, as most of the gas here comes from Canada, but yes, it all "comes from the same place."

I would love for the dealer to tell us that the cold start issues, rattling, etc. is due to bad gas. That way I could pull out the receipts and show how Daisy has received nothing but Sunoco 94 since birth (although I think I got Shell once, many moons ago on a trip down south)... my wife thinks I am crazy making her save all the receipts. I/We had always been Mobil people, mainly because I figured it was a top tier company, and I had heard of an issue from a mechanic that a gas station reimbursed for what was decided bad gas (it was not a Mobil). Unfortunately, I found my Saab to start running rough over the winter, when I finally determined it was happening with fillups at a specific Mobil station. Using the Sunoco across the street, issue went away. Figured it was the switch to "winter gas mixture," but didn't want to deal with the hassle so went all in with Sunoco.

As for cleaning, it was mentioned previously, but also wanted to throw another plug in about Chevron Techron. It is highly recommended on the Saab user forums by many members (including me), and appears to be the best additive to keep our DI Saabs going as well. Have tried to carry this over with the Mini, but the wife is not as diligent with her car (and shame on me, I don't spend as much TLC time anymore with any of our cars).

Thanks.

 

Don't worry about the top tier nonsense. Just buy the correct octane fuel from a high volume outlet like Costco so you're assured of getting ultra-fresh fuel. Then add a bottle of Techron at the specified dilution every 10K miles or so or just before an oil change.

 

I've never had a car that ran bad on shell. mobil, yes... my neon from many years ago absolutely HATED mobil. It was dark coming home one night and the only gas station I could find was a mobil someplace off i95. I knew my car was going to run bad on the way home, but I didn't expect it to literally cough and almost stall pulling out from the station.
my eclipse didn't seem to mind citgo or mobil, but it seemed to have a weird perk every now and then with shell gas. certain RPM and it'd power surge like I had variable valve timing.

so yeah, shell for me for life.

 

With direct injection I fail to see how gas can have any affect on where most of the gunk is. It's not like the plugs are fouling. Now if they said the PVC clogged up (as they do) from cheap/bad oil, maybe I would listen. Oil change every 5,000 miles and Seafoam every 10,000 miles will be in my plan for any DI engine I own.

 

I just brought my MINI Clubman in for it's 1 yr oil change, I changed it earlier myself but I still have 4.6KM left on the oil mtn meter. I also had them rotate the tires, otherwise, no issues but...............

The service advisor started on a discussion about "Top Tier Gas" and that I should visit the website for top tier gas. He indicated that on the east coast there is more of an issue with gas because many get 93 Octane and randomly, that gas has had between 10-30% ethanol. Anything above 10% ethanol can be harmful to the engine. He further went on to say that some will mix half the fill-up with 89 Octane and the other half with 93 Octane to get 91 octane. He indicated that the other Octane fuels there is better control over maintaining the Ethanol percentage and recommended that I always get 89 Octane fuel. I pointed out that I have a hard time going with advice that is contrary to what the car owners guide indicates but he stuck with the 89 Octane recommendation and said my MINI will probably get better gas mileage and better performance because the ethanol percentage is better contolled with the less high octane gasses.

What you guys think about this ?? (I had no problems. he was just passing along what the dealership recommends.)

 

I think who ever told you that is full of CRAP. All of the gas is the same when it leaves the refinary. The ethonal is added there. The other additives are added at the place where the tanker truck is filled up. That person really needs not be in a service department at all.

 

I may not go as far to say he was full of crap but it does go against my thinking. Interesting thing is that before reading your post, I noticed that a similar discussion is on the 1st generation MINIs. Rcmd read those postings before we rule out what the service advisor indicated to me.

First of all, there is a Top Tier Website that explains about what that is and contrary to what I would have thought, Exxon-Mobil is not one of those in the listing. The second thing is that on the 1st generation problems forum, one guy explains that a 91-92 Octane european grade is equal to a lower grade american gas - he uses 87 octane and he has been fine. So....I am keeping an open mind on this until i hear more weigh in on the subject.

But what is the story with BMW/MINI Cooper ? They indicate 91 Octane in their manual with no mention about Top Tier Gas. Then their staff tells a different story ?

 

I have posted in another thread the response from ExxonMobil when I asked them about Top Tier listings. Basically, they indicated that all of their gasoline products meet or exceed regulatory requirements and industry standards. They added that they did not participate in the Top Tier listings because they believe such listings contribute to confusion in the marketplace.

I can't help but agree with them when I read all these threads about Top Tier gasoline!

 

All major fuel companies with the exception of Sunoco I think, fill their tankers from the same exact tank and as ronnies948 states....various detergents / ingredients are added after. That is because Sunoco owns their own tanks.

And, unless the fuel pump is marked otherwise 10% ethenol is the norm. In fact every pump I have seen in the New England area has a large decal which reads: "No more than 10% Ethenol." So any claims of some 30 percent ethenol being sold here has to be taken with a grain of salt. And any SA using it as a crutch for unexplained engine failure or issues is just that, a crutch.

 

This is correct.

That is why I always thought it is more likely that the contaminents and other junk is introduced at the gas station. It is always wise not to fill up your car when the refueling truck is there churning up the curd from the bottom of the tank.

 

It is always wise not to fill up your car when the refueling truck is there churning up the curd from the bottom of the tank.

Actually, curd is quite tasty. It's the crud that's bad for your fuel pump...

 

Good one.