GenVibe - Community for Pontiac Vibe Enthusiasts

In my old 2003 Vibe GT I only used the highest grade gas, what is everyone else using in their GT. I know the owners manuel says use the highest grade.

yes.

You have to run premium, or else you risk engine problems...you can't mix premium and regular, or run every other tank as premium, it all needs to be premium.

Good thing I didn't get the GT then, lol. I have enough loans, I don't need one for gas too.

The highest grade of fuel available may not always be premium, as not all stations carry premium. Using a lower octane fuel in a modern computer controlled vehicle, that is designed to run on premium, will not damage the engine, just reduce the performance of the engine. If a lower octane fuel is used and knock is detected, the ECM will retard ignition timing enough to prevent engine damage (severe knock or detonation) but by doing so, the performance, that the engine is capable of, is reduced. So, the bottom line is, use the octane rated fuel that is recommended in the owners manual for best performance.

Quote, originally posted by djb383 »The highest grade of fuel available may not always be premium, as not all stations carry premium. Using a lower octane fuel in a modern computer controlled vehicle, that is designed to run on premium, will not damage the engine, just reduce the performance of the engine. If a lower octane fuel is used and knock is detected, the ECM will retard ignition timing enough to prevent engine damage (severe knock or detonation) but by doing so, the performance, that the engine is capable of, is reduced. So, the bottom line is, use the octane rated fuel that is recommended in the owners manual for best performance. well said! so if premium is to expensive, you could run regular but sacrifice performance.

You could but it's not recommended. It's possible that continued use of a cheaper grade of fuel could drop your MPG performance enough to make it more costly than using premium, in the long run. Again, use what the manual recommends but if you must run a tank full of lower octane, it won't damage your engine.

Quote, originally posted by djb383 »You could but it's not recommended. It's possible that continued use of a cheaper grade of fuel could drop your MPG performance enough to make it more costly than using premium, in the long run.THis is a good point... The difference today if there is a $.10 difference between grades is about 9% between regular and premium. If you get 30mpg with Premium but see 27-28mpg with regular, you're not saving any money PLUS you're not getting the performance you initially paid for!Some gas stations have only a $.09 or less difference between grades. For a 10 Gallon fill-up, you're only saving $2.00, at most. Whether the gas is $3.00 a gallon or $1.00 a gallon, the difference is usually still that same $2.00 for 10 gallon fill-up. Long story, short. It's a price I expected to pay when I bought the vehicle so I always go with Premium, 93 octane unless it's not available when I'm traveling, and always name brand fuels like BP, Exxon-Mobil, Marathon because there is rarely a real price difference between those and the generic named fuels.Dave

its a big missconception that premium costs WAY more then regular fuels. Take this for example. regular at the pump is $2.20 while 90 premium is $2.45. Say you fill up your tank with 12 gal of regular fuel. Thats $26.40 for a tank of fuel. Now say you put in 12 gal of 90 premium. Thats $29.40 with a difference of $3.00. Now can you honestly say (removed) I can't afford $3 more in fuel? $3.00 is a small amount in my opinion and well worth spending to keep your engine running smoothly. Trust me, repairs on your engine for using the wrong fuel is going to cost a lot more then the $3.00 you saved cheaping out at the pump.

I have a base Vibe and I'm always on the gas (within the speed limit), so it doesn't matter to me. I even waste the money on a tank of premium every once in a while for my baby.

Detonation is very easy to hear however a bunch of GenViber's have propably never heard it because they're too young. Knock sensors and ECMs back in the 80s would allow some ping but that has pretty much changed and been greatly improved over the last 10-15 years. I can't recall hearing an EFI vehicle ping or knock but that doesn't mean it couldn't happen and like I said previously, for best results, and your driving pleasure, follow the manuals instructions.

I have been using the 87 rated one lately, so not the lowest, not the highest. I think a lot of people mistake this for premium, as some stations don't have 90 or higher premium. But between regular 85 and 90, there is sometimes 20 cents or more, depends.

In Canada the difference is 10¢/litre or 38¢/US gallon between 87 and 91 octane.

Sunoco 93.

If you can find a Tesoro station, they are pretty common in the northwest, their regular octane is 90, and I never find them to be more expensive than the other guys... of course I have a base so 90 is good fer me.