In January of this year, I finally bought a “new to me” new car. For three years I had driven my grandmother’s ’89 Buick Century, tape over all of the broken tail-lights and transmission threatening to give out.

octane modelI had meant to buy a VW TDI (Biodiesel) but I couldn’t seem to allow myself to afford one. So I got a great deal on a regular-old gasoline 2000 Jetta in pristine shape, less than 65,000 miles. What I hadn’t remembered the day I bought it, is that these V6 Engine beauties are supposed to be fed 92 Octane gasoline! I have already driven up and down the West Coast once in my black Jetta, named “Dahlia” and cried about the gas prices in California. I am about to take that trip again, to Vegas, and each time I fill up my tank at home, I contemplate cheating her when we’re on our expensive vacation.

So, today, I did some research. Of Course, I went to the NPR CarTalk website to check out what Tom and Ray have to say on the subject, hoping some frugal car-lovers would let me have a little pocket book relief


Oh Well. Here’s the low-down from CarTalk:

Ray: And because you’re–shall we say–frugal, you’re going to be really bent if you ruin the engine on your new car and have to pay for a new one, aren’t you? In which case it’s very important that you follow the manufacturer’s instructions for octane ratings–whatever they are.
Tom: Here’s why. The lower the octane, the lower the temperature at which the gasoline explodes in the cylinders. And in certain “high compression” engines like yours, 87 octane gasoline explodes too early. Those early explosions are known as “pinging” and they eventually cause engine damage.
Ray: Premium gas (probably 91 or 92 octane, whatever is specified in your owner’s manual) explodes when it’s supposed to in your engine, and that’s why the manufacturer of your car requires it.”

That’s enough scary-talk for me.

Now, half of me still wants to try 89 octane in Dahlia. But I keep thinking of two things:

1. I have this daydream where I put in the cheaper gas and then my car just stops working and I take it in and say I have no idea what’s wrong and they do some little chemical test on the gas that’s running though the system and they find out and my wonderful comprehensive 3 year warranty which I pay an extra fifty-six dollars a month for will not cover the damage!

2. It seems sort of like skimping and buying a generic chemical-laden laundry detergent instead of the natural stuff and washing your sheets in it when your girlfriend is highly sensitive. She’s going to get a bad rash and you’re going to have to take her to the doctor and it’s all your fault.

When I had my buick and before gas was so expensive, I used to hope my engine would sound better if I let Bessie drink some 89 Octane when we were on road trips. I wasn’t ever sure if it did anything. If you have a car that should run plain old ’87, should you treat your car to some high octane gas once in a while to “clean out” the engine? CarTalk says , “Using a higher-than-called for octane is a complete waste of money.” You can find out why at as you learn some car chemistry.

In two years I’ll trade Dahlia in for a hybrid or (if we’re lucky) an electric. But it looks like I’ll be paying through the nose until then because I’m too afraid to hurt my engine. Good thing I love to carpool. “That will be five dollars for the gas, thank you.” It may be actually cheaper for me to rent a little honda for my long road trips, but I won’t risk ruining my engine by cheating with Octane.