Acura TSX Forum banner

1 - 20 of 23 Posts

·
, Moderator Emeritus
Joined
·
1,003 Posts
Discussion Starter #1
Unfortunately, with higher temps coming, the need for higher octane is more likely to be greater... Read on

Regular gas often fine in modern cars

Bob Golfen
The Arizona Republic
Apr. 27, 2004 12:00 AM

Are you wasting money putting premium gasoline into your car or truck?

Most people are, according to automotive experts.

Only about 5 percent of modern automobiles require premium under their manufacturers' recommendation. For the other 95 percent of the cars and trucks on the road, premium fuel makes no difference in performance or reliability.

And many of the vehicles that manufacturers say need premium run perfectly well on regular without any dire consequences or significant loss of performance.

"If you can't tell the difference, the car can't, either," said Mark Salem, a Tempe veteran auto technician and advice columnist.

"The reduction in performance can only be measured on a dynamometer. Most people, including myself, can't tell the difference."

Try telling that to Kelvin Williams, 35, of Phoenix. Despite the climbing cost of premium gas, he's still using it in his Dodge Ram pickup, he said, because regular gas "actually bogs down the car."

"Yes, I have to (use premium) with my truck, it's a Dodge 1500 Sports Edition Ram," Williams said. "With the V-8, it's better for the engine itself."

Salem said he has owned his 1995 Chevrolet Corvette since it was new, and despite the automaker's advice that premium be used, "I've used regular since Day 1."

With gasoline prices on the rise, the use of premium fuel has dropped off nationally as more motorists try cheaper blends to save money. Typically, premium costs about 20 cents more per gallon than regular.

In 2003, sales of premium represented about 12 percent of pump sales, down from 13.5 percent in 2002 when the cost of gasoline was lower, according to industry data. The highest use of premium was during 1994, when it reached 20.3 percent.

Premium gasoline is not better than regular, just different, said Randy Nowell, a master technician for the American Automobile Association. The difference is in the octane levels, a measurement of the gasoline blend's resistance to engine knock caused by pre-ignition.

"Dealers and sales people will tell you to buy premium because you're buying a premium car," Nowell said. "That's a myth."

Nearly every 2004 General Motors vehicle uses regular gas, said Chuck Harrington, GM's Western regional spokesman.

Ford now has just "a handful" of cars that use premium, spokeswoman Sandra Badgett said. But those cars can use regular with no ill effects, she said.

"We generally recommended certain octane because that's where the engine is tuned to run the best," Badgett said. "If you put regular in a vehicle that wants premium, it's not going to hurt it. It's not going to drop dead on the road."

Using premium in a car or truck that requires regular gives it no benefit in performance, mileage or reliability, she added.

Regular ranges from 85 to 87 octane, midgrades from 88 to 90, and premium 91 or higher.

But only performance engines with high compression ratios or those enhanced with turbochargers or superchargers benefit from the anti-knock protection.

The premium-gas issue has changed over the past two decades. Since 1981, every vehicle includes an electronic device in the ignition system called a knock sensor, which slightly retards the vehicle's ignition timing if it senses pre-ignition. The timing change may result in slightly less performance or fuel mileage, but it won't hurt the engine, Nowell said.

He advises drivers of vehicles requiring premium to try a tankful of midrange, . which is about 10 cents per gallon cheaper than premium and slightly boosts octane at lesser cost.

If midrange works, then run a tank of regular.

"It's not going to hurt anything if you use a tankful of regular fuel," Nowell said. "If it runs fine and you don't lose fuel economy, then use it."

European manufacturers BMW and Volvo advise premium for all of their vehicles yet state that regular can be used without ill effects other than some loss of acceleration and gas mileage.

"To get the results the cars are designed for, you use premium fuel," BMW spokesman Gordon Keil said.

Nearly every Volvo vehicle is now turbocharged and requires premium but will run without harm on regular, said James Hope, company spokesman.

A driver who is trying regular in a car requiring premium needs to listen for the telltale signs of engine "ping" during acceleration or hill-climbing. If the engine pings, switch back to premium or try the midgrade blend.

"It hurts the engine if you get a pinging and ignore it," he said.

If the vehicle is expected to perform hill-climbing, such as driving from Phoenix to Flagstaff, the driver could switch back to premium for the trip, Nowell said.

High elevations or high ambient temperatures also may provoke a need for premium in vehicles designed to use it.

Car and Driver magazine conducted a test in 2001 that determined that even most high-performance vehicles will run normally on regular with only a marginal loss of performance.

"If the car is sufficiently new and sophisticated, it will not suffer any ill effects," the magazine concluded. "But be ready to switch back to premium at the first sign of knock."

Any vehicle that should use regular but knocks on anything less than premium should be taken to a mechanic's shop for a checkup, the magazine advised.

http://www.azcentral.com/arizonarepublic/news/articles/0427premium27.html#
 

·
, Moderator Emeritus
Joined
·
10,086 Posts
Yes. However, several people (on the various TSX sites) who have tried it both ways have said there's a noticeable difference in performance AND fuel efficiency, and they sounded pretty credible and accurate.

There's also the question, ignorant though it may be, that maybe using regular might somehow be "bad" for the car, which I do worry about a bit, without having any idea whether it could be true or what it might mean specifically. But, look at what that guy says:

"It's not going to hurt anything if you use a tankful of regular fuel."

Maybe I'm picking on his wording in a way that he didn't mean, but, we're not talking about just a tankful, we're talking about what we just do. And he didn't find it so easy to commit himself that it won't hurt anything if you regularly use regular.

Maybe I'm throwing away my money, but I'll keep getting premium. And I'm pretty confident that I'm not just throwing it away, because nobody seems to doubt that at least you get some amount of better performance -- and I'm adding also that there's very little doubt that you get at least some amount of better MPG. Is that enough to justify the extra cost? To me it's a very clear yes. And if there's any real chance that it's also better for the car, that blows the whole argument for regular out of the water.

Just my :2c:
 

·
, Moderator Emeritus
Joined
·
1,003 Posts
Discussion Starter #3
Larch,

I'm sort of with you on this one primarily due to emotional/unwillingness to change mentality. This used to get me in trouble at my last company as they always espoused how "change is good."

This has become such a gray area as the manufacturers usually do not like to deviate from their stated positions for their fuel grade recommendations.

However, that said, here is what I think FWIW. Ideally, use Premium if you can. In a pinch if it's not available, use something less.

Using lower grade fuels in the TSX is probably not the best idea as the compression ratio is pretty high.

Long term, do what your conscience tells you is right.
 

·
Orangeblood
Joined
·
136 Posts
Probably right. But if you hear knocking or pinging, get some premium in that tank asap!
 

·
Guitar and Amp Junkie
Joined
·
465 Posts
You know, this is such a silly thing when I hear people using regular when they bought a premium car that requires premium fuel.

People will buy a $30K car, and try to chintz out by using cheap gas. Here are the numbers: assuming a 25 cent difference between premium and low-grade. Most cars have approx. a 15 gallon tank, give or take a few. This results in a difference, per fill, of $3.75. If you fill up 60 times a year, which is more than once per week, you would save a whopping $225 a year. Big whoop.

If 200 bucks a year is going to make or break your budget, then you shouldn't be driving a car that requires premium fuel any way. The bottom line is, in some cases it does make a difference. It makes no sense to buy a premium car and not spend the little bit extra to put good gas in it. There is a reason all cars have knock sensors -- to prevent pre-ignition, the cause of knocks and pings -- which can harm your engine over the life of the car. If it didn't, then manufacturers would not put the sensors in the car to begin with. By the time you can actually hear knocking and pinging, the problem is worse than you think since it takes a good deal of pre-ignition to cause the sounds (just because you can't hear it doesn't mean pre-ignition is not a problem in the engine).

I'm surprised they have "master technicians" quoted as saying it makes no difference, when later on in the article they say that it does -- in some cars.
 

·
, Moderator Emeritus
Joined
·
1,003 Posts
Discussion Starter #6
Surprisingly, there was a potential condition that was missed by the article.

Let's say you continually run regular fuel in your TSX or other high compression engined vehicle. Your computer has now compensated by retarding the timing to reduce knock or "ping" due to low low octane that causes faster burning in the engine.

Under these conditions you run the risk of possible engine overheating especially under load like climbing hills and higher elevations, and more so in hot weather.

The result could be a number of related issues not the least of which may be excessive carbon deposits or buildup on the pistons.
 

·
Registered
Joined
·
954 Posts
Ferg said:
You know, this is such a silly thing when I hear people using regular when they bought a premium car that requires premium fuel.
I agree with you. Why buy a premium car if you don't want to buy the gas that the manufacturer says to use? And if you already have a premium car, it's time to sell it if you can't afford to fill it up with premium gas.

In any case, I think in many cases using regular unleaded is fine... but you'll have lower performance (lower HP, lower MPG). Personally, I say use whatever your comfortable with... it's your car and you'll have to pay if you have any engine damage... the authors of that article won't.
 

·
Registered
Joined
·
332 Posts
hip said:
The timing change may result in slightly less performance or fuel mileage, but it won't hurt the engine, Nowell said.
If you get less mileage with regular gas, the cost savings is effectively less than the difference in price, since you are driving fewer miles per tank. Depending on how the numbers work out, it could cost more money.

Does the OBD black-box record the timing change? If so, a mechanic can verify long-term usage of lower octane gas and have grounds to void your warranty.

Like others said, why mess around with this for $200/year on a $26k car?
 

·
, Moderator Emeritus
Joined
·
5,757 Posts
I usually put 89 octane in my TSX cuz I don't notice a difference with middle grade and premium, plus its 10 cents cheaper. Am I doing harm to my car by doing this?:donno:
 

·
, Administrator Emeritus
Joined
·
10,660 Posts
hip said:
"If you can't tell the difference, the car can't, either,"
"Dealers and sales people will tell you to buy premium because you're buying a premium car"
These two comments made me laugh :laugh:
But only performance engines with high compression ratios or those enhanced with turbochargers or superchargers benefit from the anti-knock protection.
The TSX falls under this category, and therefor it's 91+ octane for mine ;)
 

·
, Moderator Emeritus
Joined
·
1,003 Posts
Discussion Starter #11
2004_Acura_TSX said:
I usually put 89 octane in my TSX cuz I don't notice a difference with middle grade and premium, plus its 10 cents cheaper. Am I doing harm to my car by doing this?:donno:
Controversial topic to be sure. Obviously the "experts" and no one here can tell you with any certainty one way or the other so it's really your call.

I'm sure if you ask Honda/Acura they will tell you to comply with their recommendation. So bottom line is...

"You must choose, so choose wisely" :reading:
 

·
Registered
Joined
·
6,255 Posts
I put premium in my car also, however for the last 4 yrs I have had to put premiuem in the tank (last car was supercharged)
 

·
Just a little nutty
Joined
·
664 Posts
I always try to put in the lowest manufacturer RECOMMENDED octane fuel. Per Acura website:

Recommended Fuel
Premium unleaded 91 octane or higher**
(** Gasoline with an octane number lower than 91 may be used, with reduced performance).

Since 91 octane isn't available here, I go with 93 octane. I'm no expert at this, so I just go with what Acura tells me.
 

·
, Moderator Emeritus
Joined
·
8,663 Posts
Whatchamacallit said:
I always try to put in the lowest manufacturer RECOMMENDED octane fuel. Per Acura website:

Recommended Fuel
Premium unleaded 91 octane or higher**
(** Gasoline with an octane number lower than 91 may be used, with reduced performance).

Since 91 octane isn't available here, I go with 93 octane. I'm no expert at this, so I just go with what Acura tells me.
Ditto... 93 Octane user here too..
 

·
Registered
Joined
·
1,497 Posts
Re: Re: Do you need premium?

kiteboy said:
If you get less mileage with regular gas, the cost savings is effectively less than the difference in price, since you are driving fewer miles per tank. Depending on how the numbers work out, it could cost more money.
Hmmm... ok, so let's say that you get 22 mpg with premium and 20 mpg with regular, and you go 15 gallons between fillups, and you live in NJ and the prices are $1.60/g regular, $1.80/g premium, AND you drive 15,000 miles per year. In other words, you're me :eek:

With regular, you will pay $24/tank and drive 300 miles/tank, equalling $1200/year in fuel costs.
With premium, you will pay $27/tank and drive 330 miles/tank, equalling $1227/year in fuel costs.
So by buying regular, you've saved $27.

How many assumptions did I just make???

Well, if the drop in mpg between premium and regular is only 1 mpg (22 premium, 21 regular), then the savings would be higher - $1143 in annual fuel costs, savings = $84. Ehh, not a lot of money.

That being said, I think premium fuel is a total scam. Most people who use it are putting in it cars that don't ask for it, and most cars that ask for it don't need it.

In conclusion, I use premium because I'm a tool. Oh, and my fuel economy really is that bad most of the time.


edit: above comparison assumes no drop in performance

Does the OBD black-box record the timing change? If so, a mechanic can verify long-term usage of lower octane gas and have grounds to void your warranty.
Does anything anywhere say fuel choice affects the warranty?? That's news to me. :confused: :rolleyes: :( :eek:
 

·
, Moderator Emeritus
Joined
·
1,344 Posts
Ferg said:
You know, this is such a silly thing when I hear people using regular when they bought a premium car that requires premium fuel.

People will buy a $30K car, and try to chintz out by using cheap gas. Here are the numbers: assuming a 25 cent difference between premium and low-grade. Most cars have approx. a 15 gallon tank, give or take a few. This results in a difference, per fill, of $3.75. If you fill up 60 times a year, which is more than once per week, you would save a whopping $225 a year. Big whoop.

If 200 bucks a year is going to make or break your budget, then you shouldn't be driving a car that requires premium fuel any way. The bottom line is, in some cases it does make a difference. It makes no sense to buy a premium car and not spend the little bit extra to put good gas in it. There is a reason all cars have knock sensors -- to prevent pre-ignition, the cause of knocks and pings -- which can harm your engine over the life of the car. If it didn't, then manufacturers would not put the sensors in the car to begin with. By the time you can actually hear knocking and pinging, the problem is worse than you think since it takes a good deal of pre-ignition to cause the sounds (just because you can't hear it doesn't mean pre-ignition is not a problem in the engine).

I'm surprised they have "master technicians" quoted as saying it makes no difference, when later on in the article they say that it does -- in some cars.
:stupid:
 

·
Registered
Joined
·
332 Posts
Re: Re: Re: Do you need premium?

jcg878 said:
Does anything anywhere say fuel choice affects the warranty?? That's news to me. :confused: :rolleyes: :( :eek:
From the warranty booklet:

No warranty shall cover:

1. Any repairs required as a result of lack of required maintenance.

From the manual:

... designed for 91 octane gasoline... Use of a lower octane gasonline can cause a persistent, heavy metallic rapping noise in the engine that can lead to mechanical damage.

Ok, the 91 octane part is not specifically the maintenance section, but that remains fairly tight cover-your-ass wording (for Acura) if they wanted to burn someone on a warranty claim. I'm not saying it would happen, just presenting the possibility.

Why gamble for $84/year?
 

·
Registered
Joined
·
1,497 Posts
Re: Re: Re: Re: Do you need premium?

kiteboy said:
Why gamble for $84/year?
Not saying I would, but has anyone here ever heard of a refuted warranty claim because they detected <91 octane use in a 91 octane requiring engine?? I never have, and I know plenty of people who ignore the 91 'requirement'... several of them are 1.8T Passat owners who have had engine problems fixed under warranty, and if ever there's a company with shitty service departments who bilk you, it's VW IMHO.

So until I hear of my first warranty claim disputed from 'improper' gasoline brand use, I'll have to stick to other paranoid reasons to fill 'er up with premium :D

edit: But I agree, it does sound like CYA/'told you so' wording
 

·
Registered
Joined
·
220 Posts
I have read where some TSX owners using less than premium fuel have experienced poor fuel economy not to mention less performance.
 

·
Registered
Joined
·
954 Posts
2004_Acura_TSX said:
I usually put 89 octane in my TSX cuz I don't notice a difference with middle grade and premium, plus its 10 cents cheaper. Am I doing harm to my car by doing this?:donno:
Harm? Possibly, but no one seems to know for sure. Do you honestly think that it's worth saving 10 cents/gallon? What does that add up to... $1.50 per fill up... $78 per year? Do you think it's worth it? When you say you "don't notice a difference", did you drive your car for about a month or two on each type of gas and check the mileage?

In any case, it's your car, you have to live with any potential problems that might or might not happen.
 
1 - 20 of 23 Posts
Top