BMWs do not require Premium fuel...Only recommended?

[backtoreality15]

I was with my cousin, who just purchased a 335i. The CA, when going over all the car's features at the desk, said:

"Many people believe that your BMW will require premium fuel or that it is substantially better for it, but that is not true at all. Does give it more power & economy? Sure. But is it worse for the engine in anyway? No."

And he started talking about BMWNA and some chemist doing a study, etc.
What are you guys' opinion this? Bunch of mumbo-jumbo?

[yourfriend]

I've always thought that for just driving around town getting normal gas is fine, but driving at highway speeds(or speeding on the highway) would make me nervous on anything else but the recommended.

[plien69]

Most modern engines have knock sensors, and will retard timing when it detects knocking or pinging due to lower octane, to prevent engine damage. You will lose some power, and possibly some mileage. But it should not cause permanent damage.

[mfratt]

Using low grade fuel WILL harm the long-term durability of your motor.

Plus, when I use 87 octane (usually pump 93), I get worse gas mileage, and the car doesn't feel as enthusiastic to perform as it usually does.

So, is it required? Of course not.
Then again, you could live off the McDonalds dollar menu if you wanted.

[plien69]

Originally Posted by yourfriend

I've always thought that for just driving around town getting normal gas is fine, but driving at highway speeds(or speeding on the highway) would make me nervous on anything else but the recommended.

In fact, probably the opposite is true. Cruising at highway speeds is not stressful for the engine at all. There's not a lot of load, lots of airflow for cooling, etc.

It's going around town, with it's many starts and stops, that puts more load on engines and calls for higher octane.

[scs]

this is a boosted motor, the reason the a/f graph goes way rich on high boost, is to help eliminate detonation, and keep the fuel charge cooler. higher octane fuel is less volatile, which is why you should run it in a turbo motor. if you're not turbo charged, then the knock sensors will retard the engine timing enough to compensate for the lower octane. you should always use the recommended fuel for the engine in hand. higher octane fuels are required for higher compression, turbo=increased compression at higher psi/boost levels.

[x97Melbourne]

Owners manual.....for those who haven't seen....
In the owners manual, it says 89 fuel is REQUIRED for the 135i. 91 is recommended.
For the 128i, 87 fuel is required, 91 is recommended.
I am using 91-93 fuel now for my 135i, but after the breakin period (1200 miles) I plan to switch to 89.

Thoughts???

[ScottyGams]

i don't understand springing for the nice engine and cheapening out on fuel... you lose performance...

the 135i is an enthusiasts' car, people who pump regular are not enthusiasts. There are other ares of life you can cheap out on.

I chose bathing!

[Robert]

Nice catch on the details. Thanks for the info, Melbourne

[60Driver]

Yeah, good catch. I use premium but I'm going to review the owners manual again for the octane numbers.

[scs]

40-50k turbo charged luxury car (recommended fuel premium)

debating whether or not to spend an extra buck fifty every fill up...is this really happening?

[mfratt]

Originally Posted by scs

40-50k turbo charged luxury car (recommended fuel premium)

debating weather or not to spend an extra buck fifty every fill up...is this really happening?

Well, to be fair, its more like $4.

[ky_soldier]

Originally Posted by scs

40-50k turbo charged luxury car (recommended fuel premium)

debating weather or not to spend an extra buck fifty every fill up...is this really happening?

+1

[Topsupra]

You should run premium fuel, specially on a turbo car no question about that....

Now can you run 87 regular, sure the car will run but you will loose performance, and if you plan on doing any mods like ecu (boosting turbos) exhaust, etc. You must run premium or you can damage the motor. But even if you don't plan on doing any mods you should still run premium fuel. Besides most people buy the 135 over the 128 for performance so why would you put the cheaper fuel....


Jay.S

[E82tt6]

The motor will likely go into limp mode, or close the throttle, pull timing, and open the wastegates to retard knock.

[Qube]

Really? I can pump 89 into the 128? Interesting. I never saw that in the manual...

[Nixon]

With the price of gas getting press coverage on the nightly news on a regular basis, even BMW CA's are trying to find an angle on the issue to boost sales.

CA's know that telling folks they COULD use lower octane fuel if buyers wanted, will help lower buyer's anxieties. It plays into the whole rising gas price story that plays out over and over in the news. Whether you are selling cars that are 15k or 50k, CA's know they will run into SOME buyers who don't like the idea of being stuck for a few years with a car that requires premium -- at a time when gas prices seem to be exploding out of control.

Talking about the fact that BMW's (and all ODBII vehicles) are FULLY protected from engine damage when lower octane gases are used is just part of this CA's sales schtick. If it helps the CA with just one sale a month, it might be worth adding to the CA's sales routine. Regardless of whether any of the CA's customers actually used lower octanes or not. It's all about alleviating any possible buyer anxiety, and playing into the latest news headlines. It's a savy sales technique, nothing more.

For example, look at the BMW ads on TV now that talk about all of the models that BMW sells that get 28+ mph. The same argument could be made about MPG. As in why would BMW buyers who regularly spend 50k+ buying a car worry about a few bucks at the pump? But it isn't about logic. It's about marketing and playing upon the hot car topic of the year that is being driven into people's heads over and over. Gas prices.

But when it comes right down to it, the CA is correct. You DO NOT have to use Premium gas in either turbo or NA 1-er's. It's not going to go into full limp mode, it's just going to trim back the power seamlessly without allowing the engine to be damaged.



Side note: Low quality gas and low octane gas are two different things. You can buy a high quality gas (Shell, etc) in different octanes, and it is still high quality gas at all octane levels. The inverse is true for low quality gas. Low quality gas of any octane level really can harm your car (cats, fuel pumps, valves, etc). That's an entirely different issue.

[aus]

Car sales people are generally idiots. I ALWAYS know more than any BMW sales person I've talked to, but you're guy is a true dumba$$ for telling you it's OK to run regular fuel in a turbo car designed for Premium.

[Lester]

What about running 89 with an octane booster additive?

[Steve135i]

Originally Posted by scs

40-50k turbo charged luxury car (recommended fuel premium)

debating whether or not to spend an extra buck fifty every fill up...is this really happening?

I agree 1,000,000%%%.





Unbelievable. SPEND THE EXTRA..






GET 93 OCTANE, GEEZ...

[imported_Shawn]

Originally Posted by x97Melbourne

Owners manual.....for those who haven't seen....
In the owners manual, it says 89 fuel is REQUIRED for the 135i. 91 is recommended.
For the 128i, 87 fuel is required, 91 is recommended.
I am using 91-93 fuel now for my 135i, but after the breakin period (1200 miles) I plan to switch to 89.

Thoughts???

I will have to look more closely at my R53 owners manual, I thought that minimum 91 was required. Based on that, I would have been certain the same would be true for the E82. I have been so used to filling with premium, and since it is "recommended", I don't think I would feel comfortable filling with anything but. Just mental insurance, as I saw posted elsewhere in this forum.

[imported_Shawn]

Originally Posted by aus

Car sales people are generally idiots. I ALWAYS know more than any BMW sales person I've talked to, but you're guy is a true dumba$$ for telling you it's OK to run regular fuel in a turbo car designed for Premium.

I agree with that. If I hadn't lived all over this country, I would have thought it was just the S.A. CA. However, it would be a refreshing change of pace to find one that was knowledgeable, and the icing on the cake would be one that was knowledgeable AND an enthusiast to boot.