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General discussion

Gas...

Jan 6, 2008 5:45AM PST

So I have about a 14 gallon tank in my 94' Honda Accord. I reset my mile thingy every time i fill up. I would get about 360-370 miles per tank. All of a sudden, it just went to 340, and now i get 320 or less. Does anyone know of any reasons why this would happen so suddenly? I changed my spark plug wires and that didn't help. So i don't know what to do. I don't have much money and can't afford to take it in.

Discussion is locked

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Not much you can do
Jan 6, 2008 7:45AM PST

The bad news is, unless you can detect a real engine malfunction that a technician can find and deal with... you would likely waste time and money taking it in.

The good news is, it likely is not your car. The problem could be your gas. And in fact, likely is.

Have you changed brans of gasoline? Not all gas is the same. Some crappy brands are cheaper, but get worse gas mileage. If you did change, go back to the old brand, and see if mileage improves.

Have you changed what type of gas you use? Regular or Premium? Some people try to save money by buying regular, when their car needs premium, then complain about bad gas mileage. Do not do this. Buy the gas your car is designed for.

Finely, there are two things you can't change. In the winter, gas companies reformulate their fuels to deal with colder temperatures, like making gas more evaporative and less prone to water condensation. These added chemicals can reduce gas mileage.

Second, the amount of Ethanol mandated to be used in fuel was recently increased. Ethanol does not have as much energy as gas. Therefore more Ethanol in the fuel means less gas mileage.

Bottom line, unless you have a malfunction light coming on, or poor engine performance, stalling, misfires, hard starts, do not take your car in. Whatever problem will cost far more than worth to fix. This assumes the problem is your car and it likely is not.

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ok
Jan 6, 2008 12:56PM PST

Well it all happened while using the same gas. I used safeway gas and would get the good gas mileage but then one week it dropped a lot. Now i use Chevron gas and its not doing any better.

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The worst part is...
Jan 6, 2008 1:13PM PST

In the rare chance it is a mechanical problem, it will show up at some point. Still don't take it in until the problem shows up, otherwise you'll end up with the shop playing the

"it might be this. We'll try it, you pay for it, hope it works for you"

Game. Trust me, the money savings on gas isn't worth the expense.

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Well..
Jan 6, 2008 1:40PM PST

It has to be something mechanical if it happened over one week.

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don't worry about it
Jan 10, 2008 11:59PM PST

You already changed the plugs. it's a 4-cylinder, so you'd notice a misfire. But it's more than likely the winter gas.

Like Andy said, don't worry about it unless you are actually having a problem with your car. Dropping 2mpg is not a car problem and is not anything mechanical.

If you really want that 2mpg back, on the next two fill-ups, buy a jug of the STP fuel injector cleaner and a jug of octane booster on the third. They are about 8-10 ounces and can actually help, they only cost a couple of dollars, so money isn't a big factor there.

If it's a problem with your car, a small change like that with an older one especially, is probably gunked up fuel injectors, fuel filter or pump. Replace the fuel filter if you can't remember the last time it happened. That will probably bring mileage higher to what you got before. Don't worry about the pump unless the car starts stalling or stuttering.