Type of Fuel

"Tina" sez:

will it make a difference if I

Yes, you'll have more money in your bank account. :-) Other than that, the difference is negligible.

Good refuelin' to ya, VLJ

I doubt if the Camry needs premium ... she's wasting $$. Run regular in the Taco.

RTFM

"If it starts to knock I know to switch to premium,"

Wrong answer. Spark knock in any modern computer controlled engine is caused either by one of the electronic gizmos failing, or serious carbon buildup in the combustion chamber.

Both of you will do fine running 87. There is no advantage running premium in an engine designed for 87.

Ken

T> My neighbor and myself had a discussion last evening, she owns a 2003 Camry,

Tina: The computer in the truck adjusts to the gasoline you use, and Premium is not needed. It will run just fine on regular, and save you a LOT of money over the long haul.

There are only a few high-performance sports cars built where you /must/ run Premium. Or people who have added turbochargers or superchargers to their cars.

If you use Premium in a modern car or truck with EFI, the computer can sense it (knock sensor) and advance the ignition timing a few degrees, but you won't be able to tell the performance difference in everyday driving. You will pick up something under one horsepower, which might get you to the top of a steep hill a quarter second faster

- big whoop. Save your money.

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I think more then that. When pulling a long grade in my '93 3L, I notice it start to knock and ping, then it will stop with a noticeable power drop. That's running the cheap stuff.

Drive an '05 Tacoma V6 yet?

Those of us in some states, due to custom fuel blending, really have to run Toyota recommended premium to get the best power and mileage.

I stand corrected thanks Ken, I keep forgetting that I also own a 68 Vw Bug and that does get spark knock from regular gas or if it isn't tweeked just right, got to run premium in that baby ,no electronic gobble e goop on that car.

Tina

Thanks for all the replys...I'll inform my neighbor but knowing her she won't believe me, I'll tell her to ask the dealership mechanic

Tina

don't know what that means "RTFM "

Tina

Sorry, _R_ead _T_he _F_ine _M_anual.

Except the "F" often dosen't mean "Fine".

Another suggestion? Google!

RTFM:

Corolla Octane Requirement:

Product manufacturers spend time and money writing and printing manuals that are chock full of information. Sadly, these manuals often go totally unused, and are sometimes thrown away on the day of purchase.

Chances are, the vehicle's manual states a fuel requirement. In some cases, there may be several different fuel recommendations, with the conditions, such as optional equipment, altitude, or the specific usage for each requirement spelled out.

You'll notice that several people in this thread stated that premium fuel is never necessary and a total waste of money, unless you're driving something that is barely street legal. You and I have the same truck, each with a different engine. If you check your manual, which is the same book I have, you'll notice that they aren't correct for one of the trucks. One of us should at least try premium, the other has no reason to use anything other than 87.

Did you know that some manuals are considered so useful that the object can't be legally used unless you have the manual, and students learning to use the object actually are required to buy their own personal copy as part of training?

Modern closed loop engines have high compression and really need more than 87 octane to do their best, The vehicals ECM will try to let you run low octane fuel by retarding the spark to control knock but when it does this it is also reducing power output and MPG too. Give the price of fuel these days and that even plus is only 3 or 4 % more than regular it is kinda silly not to use better fuel because it may actually be cheaper to use it because of increased engine efficency, especailly in hot weather.

Well I did read the f------ manual.............ha!...too many acronyms so little time?

Tina

message

Unless the manufacturer specifically "requires" premium, run regular. A lot of manufacturers "recommend" premium, but that is just a marketing ploy cooked up by gas companies.

Occasional pinging under load like going up hill or hard acceleration or towing is normal for a lot of cars, and some owners manuals actually say that. If the engine timing is tuned for optimum performance and gas mileage, the timing advance is set to spark just before the gas prematurely ignites due to heat and compression while the intake valves are slightly open on the compression stroke (causing the ping). You can always back the timing advance off to stop pinging but that will just reduce performance and mileage. Premium gas stops pinging because it requires more heat and compression to ignite without spark and is not as susceptable to premature ignition.

If your car is p> >

Just back off the timing advance in your VW (move it closer to top dead center) to stop the ping aka premature ignition while running 87. You might lose a tiny bit of performance, but you will save a lot of money. Most performance loss is in people's head. There's really not a lot of difference in octane of 87 and 93. There are so many other factors involved and specific to the engine that affect horsepower other than the type of fuel you run.

T>

Right. Got a tinfoil hat?

My Tacoma not only runs better on 91+, it gets about 10-15% better mileage, negating the extra 20 cents a gallon.

I've tried both, measured both, it's not just about pinging.

The other three vehicles I regularily drive "recommend" 87 octane in the manual. They run fine on Connecticut's blend, the Tacoma dosen't.

First of all, comparing the two vehicles is silly, so forget what she does with her car.

My Taco knocks slightly on regular, and has since the day I got it. So, I use the middle grade (89 octane). That also gives me better highway mileage, almost 35 more miles per tank, so paying an extra $1.60 per tank doesn't bother me. Others can expound more on this, but I understand that altitude, temperature and specific brand of gas are factors. So, you have to listen carefully to YOUR vehicle and determine if 87 octane gas is sufficient. I suppose it goes without saying that you should have your radio off, windows shut, heater fan on low so you can hear what's happening. Knocking is clearly different from other sounds, but often very faint. Listen while accelerating with varying levels of "urgency".

Your manual specifically says that 87 is fine, but if the engine knocks, and the dealer finds nothing wrong, switch to 89 octane. As far as premium, I've found that it DOES give me better mileage, but only if I'm towing my boat in very hilly areas. Other than that, I don't think it's worth it.

good advice...thanks...my truck doesn't have 600 miles on her yet! She's peppy considering I traded in a 1994 ford ranger, with only 72,600 original miles on it

Tina