Premium Fuel.

[albertGQ]

My car does not require premium gasoline, but I try to fill up my tank with the good stuff twice a year. Usually once in the summer and once in the winter. The reason I dothis is because my buddy told me years ago that it is good for my car and I have to do tuis two times annually at a minimum. I'm just curious to know if I'm wasting my money or if this is a good practise for me to continue.

This is not something I need to know, but it is definately something I'd like to know.

[schteve_d]

I kind of do the same thing, I guess. Whenever I drove home to BC and am going through the mountains I will put a couple of tanks of the good stuff through it when I'm hitting the passes and working the engine. The rest of the time I just put in regular.

Don't know if it does any good or not, but I always feel like it'll clean things up a little while the engine is really working up those big hills.

I go home twice a year - once in the summer and once at Christmas - and usually drive so I can take the dogs. That ends up about the same, twice a year but four tanks or so.

[Mr.Coffee]

I'm pretty sure premium fuel burns easier and therefore requires less work from your engine but I could be wrong and am definitely no mechanic. I've heard it cleans your engine too, but I'd also be interested into the exact reasoning as to why this is good for your car if somebody knows it.

[BlackArcher101]

You are wasting money. Period.

[schteve_d]

Originally Posted by BlackArcher101

You are wasting money. Period.

You sound pretty sure. Why?

[BlackArcher101]

Originally Posted by schteve_d

You sound pretty sure. Why?

Because the high octane level of premium gas does nothing for mileage or cleaning abilities. It's simply for knocking in high compression engines.

I recommend this for a good read: http://en.wikipedia.org/wiki/Octane_rating

If you really want to flush/clean the fuel system or injectors, get a bottle of the cleaner fluid from Canuck Tire and put it in your empty tank before filling. Do this a couple times a year.

[T@T]

Originally Posted by BlackArcher101

You are wasting money. Period.

This

/thread

[DownhillGoat]

Wasting money. Some guys do the same thing with diesel to clean things out too (which makes a bit more sense as it actually burns hotter - I still wouldn't recommend it). Depends on the car, but on newer vehicles, some actually perform worse with premium fuel, depending how the OBC is mapped. Follow your manual's guidelines on what grade of fuel it recommends. If it's premium, use premium. If it's regular, use regular. If it suggests either (or higher), you're always better off with the higher octane content (used regularly, not every 6 months). Toss in some seafoam every other oil change to keep things clean.
- - - edit - - -Forgot to hit the post button. Looks like I'm a little late to the party.

[schteve_d]

Originally Posted by kunkstyle

Some guys do the same thing with diesel to clean things out too...

Years ago my girlfriend had a Tercel with a funky feedback carburetor that no one could seem to tune right. It was a known problem that resulted in premature carboning of the valves that ultimately led to an irritating hesitation. At one time there was a Toyota service tip to shoot the valves with crushed walnut shells. Anyway, a mechanic at Toyota told us to add two bucks worth of diesel to every full tank (again, long time ago!). We did, and that little car ran great for the rest of it's life.

[metallicat]

What about in vehicles in which the manual recommends premium fuel? My bike for example...am I wasting my money? The manual says 87 is OK, but 91 is recommended.

[Ironhorse]

Originally Posted by oilers_fan

What about in vehicles in which the manual recommends premium fuel? My bike for example...am I wasting my money? The manual says 87 is OK, but 91 is recommended.

That means put in 91 whenever you can. With most new cars, the OBC can accommodate 87 octane fuel by changing the timing if it needs to, but this should only really be done if 91 is not available when you're filling up, as it is a bit hard on the engine.

[worth]

OMG. You are wasting an extra $8 per year. Stop it right now!

[Bill Bumface]

You'll get worse fuel economy and performance with premium fuel as it has less specific energy.

Its only for cars that have high compression ratios/advanced timing.

If your car says that you can run 87 but 91 is recommended, you'll get better performance out of 91 and should always fill with that unless you end up in a jam.

Because of Calgary's high altitude you can likely get away with running one grade less than recommended and still get maximum (actually a bit better than with recommended fuel) performance.

[Bring_Back_Shantz]

Originally Posted by schteve_d

I kind of do the same thing, I guess. Whenever I drove home to BC and am going through the mountains I will put a couple of tanks of the good stuff through it when I'm hitting the passes and working the engine. The rest of the time I just put in regular.

Don't know if it does any good or not, but I always feel like it'll clean things up a little while the engine is really working up those big hills.

I go home twice a year - once in the summer and once at Christmas - and usually drive so I can take the dogs. That ends up about the same, twice a year but four tanks or so.

When you're going through the mountains, i.e. driving at a higher altitude, there is even less reason for you to use premium.
The idea with premium is that it is more resistant to detonation (ie premature ignition, or knocking), and hence allows for cars to use a higher compression ration, or artificial aspiration such (turbo/super chargers). When you're at a higher altitude and you've got even lower ambient pressure, the chance of knocking is even lower, so you adding the premium isn't doing a darn thing. In fact at high enough altitudes you can actually wind up with imcomplete combustion due to the higher octane, meaning lower fuel efficiency, and more carbon deposited in your engine.

Originally Posted by Mr.Coffee

I'm pretty sure premium fuel burns easier and therefore requires less work from your engine but I could be wrong and am definitely no mechanic. I've heard it cleans your engine too, but I'd also be interested into the exact reasoning as to why this is good for your car if somebody knows it.

That's a pretty simplified way of saying the exact opposite of what the reality is. As I said, a higher octane rating indicates resistance to auto ignition, so in reality it's actually regular that "burns easier".
As for the part about requiring less work from your engine, there really isn't a single part of that that makes any sense.

[Super Nintendo Chalmers]

Originally Posted by schteve_d

You sound pretty sure. Why?

The higher the octane rating, the less likely it is to prematurely combust (ie. knocking). That's an issue in cars with high compression ratio or high redline. These are more likely found in performance cars. High octane gas does not burn cleaner or improve gas mileage.

[Super Nintendo Chalmers]

Originally Posted by worth

OMG. You are wasting an extra $8 per year. Stop it right now!

I pay an extra $0.12 per liter for 91 octane. That's close to an extra $8 per tank.

[CalgaryFan1988]

I have a Pontiac Vibe GT with the Toyota Celica GTS engine. It calls for Premium gasoline, if I put in regular gas the check engine light comes on. I was told that it is because of emissions sensors in the car. I put Premium in and a couple tanks later the light goes back off.

[T@T]

Originally Posted by worth

OMG. You are wasting an extra $8 per year. Stop it right now!

I take it you don't drive much?

[DownhillGoat]

Originally Posted by CalgaryFan1988

I have a Pontiac Vibe GT with the Toyota Celica GTS engine. It calls for Premium gasoline, if I put in regular gas the check engine light comes on. I was told that it is because of emissions sensors in the car. I put Premium in and a couple tanks later the light goes back off.

It's not the emissions sensor that gives you the CEL. It's the knock sensor. You can run a chip to re-map it to regular fuel, but I wouldn't bother. You've actually got a pretty high compression ratio in that, IIRC, with it being the VVTL-i.

[DownhillGoat]

Originally Posted by T@T

I take it you don't drive much?

As per the OP, it's only 2 tanks a year. Not every fill. That's about $8 a year on a 60L tank...