Premium Gas?

[RyeHigh]

HelloI'm driving an '03 GT and wondering how important is it to use Premium Gas.If I don't will the engine fall out of the car?Any advice would be great thanks.

[VibeSalsa]

First, welcome to GenVibe!In a Vibe GT, you HAVE TO use premium gas as stated in the owners manual. The engine has been designed with 91 octane or higher.For more information see: http://forums.genvibe.com/zerothread?id=3421 http://forums.genvibe.com/zerothread?id=6520

[DopeVibeGT]

Yes, it's very important. Timing and such are involved, so use that 91+.

[vibegt11]

Try a gas mileage test. Fill it a couple of times with regular unleaded and figure out the MPG ALONG with the cost for the cheaper gas. Then fill it the same amount of times with Premium and do the same. I bet you'll find your gas mileage is worse with regular, and in the end, your 'cost permile' is darn near equal. Might as well run Premium and get the advantage of the better performance!

[DoughBoy]

don't these engines have knock sensors that will compensate for lower octane levels? I'm of the opinion that it's not bad (short term anyway), but the incremental cost required for premium gas isn't worth the performance drop.Using some Canadian numbers here:100km @ 87 octane (say, $0.7/L) = around $8 (assuming mixed driving averaging 8L/100km)100km @ 91 octane (usually $0.1 more than 87) = $1 more every 100km (if you believe my mileage numbers).Now, using the lower octane hinders performance, so your engine will (in theory) work harder to deliver comparable performance to the higher octane. Engine working harder = worse mileage = less savings.I'd stick with the premium gas.

[ragingfish]

It's not good for the engine to use lower than 91 on an extended basis. If you can't get 91, then put in lower, and yes, the engine will compensate. However, in the long term, you're not helping the engine, but while I"m not an expert, my instincts would say you may hurt it eventually...

[DavidPIL]

Hi everyone...Ok, I know this is off topic sorta but was just something I was thinking about...A few things to consider... Around here there are stations where the difference between each grade of gas is 9 to 10 cents per gallon. There is a Marathon, a SuperAmerica and a Clark station where the difference between 87 and 89 oct is only 2 cents but the difference between 89 and 92/93 is 10 making the difference between 87 and 92/93 oct only 12 cents. You might be able to find a gas station like this where the difference isn't so much. Also, it might not mean as much to the folks up North because it does seem the price of fuel is more up there but a 12 or even a 20 cent difference between low grade and premium really isn't as bad when the gas prices are higher... Basically, if 87 oct was $2.00 and Premium was $2.20, the Premium is 10% more but if the 87 oct was $1.00 and the Premium was $1.20, the Premium is 20% more. I know this doesn't mean much for most of us who are on a tight budget no matter what the gas price but as the price goes up, the difference in price really isn't as bad, if you think about it.Dave

[ragingfish]

Out here I usually go to Wawa, Shell, Remington, or Hess, sometimes Mobil. Depends on what's in the area. I monitor my MPG numbers closesly, and have not noticed any significant difference in performance using any particular fuel brands.That being said, I go where it's cheapest.

[DavidPIL]

Hi Silver...I think I would go with Mobil if they had a lower priced premium around here. When I'm traveling to SC, I only use Exxon/Mobil but locally, it's Marathon though I sometimes use the SuperAmerica when I don't want to drive 10 miles further down the road. I agree that some gas just doesn't make my vehicles run right. With my Ranger (I think that's what you have), I would have to put 89 octane in. No low grade would work, mileage would be noticably down and it would knock like crazy. Only 2 cents more for the 89 octane made it not so bad.I use the Marathon locally because it's one of the only local Premium fuels that don't add 10% Ethanol. I tend to get 1-3 more MPG with it and it just seems like the Vibe runs better. The Mobil Premium is 8 cents more per gal than the Marathon so it all works out in the end.Dave

[Jahntassa]

I seem to be sticking with Amoco recently... I used to do Texaco..but management changed at the local one when it switched to Shell..so..yeah.Nothing scientific on my part..

[Raven]

Quote, originally posted by DavidPIL »I use the Marathon locally because it's one of the only local Premium fuels that don't add 10% Ethanol.What's wrong with ethanol? Modern vehicles are made to accept it and it's environmentally friendly. I buy ethanol whenever I can. Around here we have regular gas with ethanol in it and it is the same octane as a medium grade fuel, but the same price as regular.

[pmh013]

Don't put an ethanol blend in. It's not recommended by GM. I think it says that in the manual, actually.GM tried to blame my catalytic converter failure on an ethanol blend, until they learned I'd only put in 1 tank of the stuff.Supposedly it contains stuff that gums up the works. Nothing scientific, but that's what the auto manufacturers claim, and they're the ones you've gotta deal with when it comes to warranty. The fuel companies say it' OK, but they're not the ones honouring warranty.

[drunkenmaxx]

so, why then, does quicktrip promote their gasoline so confidently? i would believe ethanol to be a good thing. it is a form of alcohol right? how in the hell could alcohol clog anything? it is thinner than water!

[FusionVGT]

It's so clean you can't carry straight ethanol in the current gas tankers. It disolves all the crud in the tanks which contaminates the ethanol.

[pmh013]

I'm not familiar with QuickTrip... I am guessing it is a station? We have only 1 station in my area that has an ethanol blend ... Mohawk.It's not the alcohol that gums up stuff, but the additives they need to put into ethanol-blended fuels. I'm no chemist, so I can't tell you which ones they are, just what GM has told me.According to the 2003 owner's manual (which you can access in this thread http://forums.genvibe.com/zerothread?id=1010), page 6-5:Quote, originally posted by GM »Your vehicle was not designed for fuel that contains methanol. Don’t use fuel containing methanol. It can corrode metal parts in your fuel system and also damage plastic and rubber parts. That damage wouldn’t be covered under your warranty.Notice that it says METHANOL. Methanol & ethanol are 2 different things (according to the fuel companies). GM says that ethanol is OK in the manual, but the person on the 1-800 line said it's not. I don't know. I have a feeling that no one really knows. Either way, I'm just going to steer clear of it.

[Raven]

This looks like a question for MadBill to answer. I'll see if I can get him on his shoe phone!

[drunkenmaxx]

Quote, originally posted by pmh013 »I'm not familiar with QuickTrip... I am guessing it is a station? We have only 1 station in my area that has an ethanol blend ... Mohawk.quicktrip is the biggest gas station in this entire area, it is preferred by pretty much anyone. they guarantee that if their gasoline causes a prob w/your car, they will fix it for free! also known as QT.

[ragingfish]

Quote, originally posted by Sunny »This looks like a question for MadBill to answer. I'll see if I can get him on his shoe phone! Lower the cone of silence! But back on topic, IMHO, if the manual says it is ok (or doesn't say it isn't ok), then go for it. If you develop problems (which I doubt is likely), pull out the manual and say "it ain't say I no use this stuff!" and then it's their problem!

[DavidPIL]

Hi Sunny et al...It might be more a personal preference or noticed by my own experiences but I don't have a problem with ethanol nor have I heard it cause a problem in vehicles at all. I have however noticed that I get a slightly better performance when I fill up with a fuel that doesn't contain it. Maybe it's a placebo effect, I dunno. If it added to the fuel causes it to burn cleaner then I'd have to assume it's not going to increase performance at all. Most things added in cars that help emmisions makes the car a bit less in the performance area, right? Just assuming here and you know what happens when someone assumes... heheheI've just read good things about Marathon fuels. Heard that it's one of the only refiners that don't use Middle-East crude. Heard it on CNN or something like that. That has to be a good thing, right? So, I go to Marathon when I can. Might not be a cleaner burn but it seems to make my VibeGT happy.Dave