gas questions for LS430

Not yet.

You can use regular (87 octane), but the engine anti-knock sensor will retard the timing to avoid detonation (pinging) which would be hard on the pistons and connecting rods. This will result in lower gas mileage, and in fact will cost you more than using the recommended octane level, as the reduction in mileage is greater than the increase in gasoline cost.

Using gas rated lower than 87 will also work --I've never seen any published limit, but performance will really suffer, and you will probably void your warranty.

On Fri, 19 May 2006 17:45:17 -0400, Jay Somerset graced this newsgroup with:

oddly enough, I get the same lousy mpg (18.5) on my 02 LS430 regardless of the octane level I fill the car with.

Premium is recommended. Why would someone buy a Lexus and be cheap on the fuel? For those people, I would recommend the Avalon.

Ummmmm....maybe because the "premium" recommendation isn't based on an engineering requirement but instead on a marketing perception?

It's legitimate to ask if the engine and its management system is designed around premium fuel, or if it's just something that marketing came up with to try to distinguish the brand.

It's not a matter of being "cheap" on fuel. It's a matter of using the fuel that the engine and its management system were designed for--not the fuel that the marketing people want to convince their buyers should use.

Toyota does not market premium fuel. They market the cars that they produce. They engineered the engine with the high octane.

The false marketing you're speeking of is something totally different. Oil companies do market "superior" cleaning with their premium fuels and never indicate anywhere that the same detergent is on the 87 octane fuel. In that regards, noone will benefit from putting premium fuel on a car designed with 87 octane in mind.

When a vehicle is specifically engineered for premium fuel and recommends it, going against that is being merely cheap. Toyota knows this. That's why they design certain engines with that in mind. The Camry is an example.

With Lexus, they market a "lifestyle experience". Absolutely they would tell their customers that the car requires "premium" gas.

We all know there's nothing "premium" about the gas, but the gas companies have spent years saying there is and people are buying into it. Witness all the people who come to places like this wanting the "best" for their Hyundai, for example, and tell the world how they therefore use "premium" gas.

Lexus marketing wouldn't dare let their customers think there's anything "regular" about the Lexus auto.

So it's a legitimate question to ask. "Premium" fuel isn't premium at all; it merely has more anti-knock properties. So, is the ES model that calls for "premium" fuel any different than the Camry model, with the same engine, that *doesn't* call for "premium" fuel? Or is the call for "premium" fuel simply a marketing gag?

I work for a very large company in which it's clear that marketing has a very large say in how things are done. Technically, there's no reason why something can't be done--but we don't do it, and it's a disadvantage to our customers, and we create that disadvantage PURELY for marketing reasons and nothing else.

It's not uncommon at all.

Yep. But searching for the truth behind the recommendation for "premium" fuel isn't being cheap; it's being realistic.

Lexus does not specify premium fuel to increase the "feeling of luxury" in being a Lexus owner. Iy probably DOES engineeer the cars to use premium fuel, as it (rightly) assumes that lexus owners can easily afford it, and won't object to having to pay the extra cost.

Is isn't "marketing hype", but it my well be good "marketing strategy".

but they don't tell owners of all models to use premium

there certainly is a difference, the question is that with the engines in use today that are equipped with anti knock sensors and computers that adjust the spark and combustion levels is premium always needed, as far as I am concerned the answer is no.

crapola, maybe some people with ego issues buy into that crap but most people who are secure with they way they are don't fall into an image trap.

Balance of nonsense snipped

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Well if you push the performance limits of the automobile, premium IS a must ... under less demanding conditions, it is more likely a waste. The US Marketing machine not only condones waste ... it encourages it! I challenge ANY automobile used exclusively for local runs to perform any differently on different formulations... On the highway you ARE most likely to see benefits (to some degree). The gasoline combustion engine is just NOT all that efficient.

I see a lot of "probably" in there; it sounds like you WANT to believe the "premium" hype put onto higher octane fuels.

Of *course* the marketing people are creating an image, that of a "feeling of luxury"--and part of that is connecting with the gas marketing of "premium" gas (which isn't premium at all).

It makes sense to ask why the ES would ask for premium fuel when the same engine used in the Camry doesn't. Hmmmm...........nah, that would have *nothing* to do with a "lexus=premium, toyota=regular" marketing push from Toyota, would it??? Nah, that would be cynical....

Right. Exactly. Well said.

The Lexus build quality is (or at least was) unchallenged. But the stuff surrounding it is pure smoke and mirrors. Of *course* they want you to think you bought a "premium" car, so they surround it with "premium" smoke and mirrors. Gas? "Use premium" (even though the "premium" fuel is nothing more than higher octane and there's nothing "premium" about it). Service? Come to our "premium" service department where, for a mere $150, you can have your oil changed while you sit on our leather couch and watch our 80" plasma TV and drink our coffee.

The base engineering is very good, the marketing stuff is just smoke and mirrors. And it's legitimate to ask: where is the line between base engineering and marketing? Did the engineers change the hardware and engine management computer on the ES, for example, to make it sufficient different from the Camry that it requires a higher octane fuel? Or is that part of the marketing smoke and mirrors?

All legitimate questions. Those that just buy into it blindly are chumps.

it just like they used to say, you don't sell the steak, you sell the sizzle

WARNING: NEVER USE 1800FLOWERS.COM They can't deliver as promised

The 3.3 liter 3MZ-FE V6 is used in both vehicles, but as I understand it Toyota tests the Camry with regular and the Lexus with premium, thus the engines have diffferent published power output and fuel requirements. My guess is that if you ran the Camry on premium you'd get the advantage of the additional power, and vice-versa.

That doesn't make any sense. They "test" it with only one fuel, therefore that's what they put in the owner's manual?

The engine management computer has an air/fuel map in it, a map which was designed by engineers. THAT'S a very, very large determinant; in fact, the fuel/air map is designed around certain parameters, the octane level being one of them.

So the question is, are the maps the same for both engines, or did Lexus specifically use a higher octane gas when designing its engine management?

It's still a legitimate question, one which has never been answered.

Most ASE-certified mechanics will (correctly) tell you that if your vehicle runs fine on a lower octane fuel that to use a higher octane fuel is wasteful extravagance.

However, it is a documented fact that premium fuel will, under sustained highway driving conditions, result in better MPG for most vehicles, not just the Lexus LS. Whether the improvement in fuel economy justifies what is currently a 20¢ per gallon difference is unclear. At $3 a gallon you would need to achieve at least 15% improvement in fuel economy for it to be worth the extra money.

Translation: at 20 mpg (assuming 87 octane regular) you would need to achieve 23 mpg or greater to cost-justify the higher octane fuel.

Stated another way, if you're achieving 20 mpg today with premium, a drop to 17.4 mpg with regular would be economically a 'push'.

Finally, don't confuse the difference between regular and premium grades of fuel with the difference between brand names and the off-brand stuff you find at Krogers & WalMart. IMO you will generally be well-advised to stay with name-brands.

Incorrect. The required improvement in fuel economy is 6.7% ($0.20/$3.00)

Same error. An mpg of 21.3 (106.7% of 20 mpg) would cost-justify premium fuel.

you wanna show us that "document", or will you just spout and leave?