Dear Tom and Ray:

I am driving my first fuel-injected car. A friend told me to be sure not to run out of gas, because it is a problem with fuel-injected cars. Is it? - FloydTOM: I've got news for you, Floyd. Running out of gas is a problem no matter what you're driving!

RAY: Actually, Floyd, your friend has probably had to replace clogged fuel injectors at some point in his life, and he's trying to help you avoid a similar fate.

TOM: The problem with running out of gas in a fuel-injected car has to do with the sediment at the bottom of your gas tank. Small particles of dirt and rust are concentrated there, and when the fuel pump sucks them up, some of that dirt can work its way past the fuel filter and, ultimately, to the injectors.

RAY: Although these contaminants are not very big, they're big enough to clog fuel injectors, which is why the fuel filter is so vital.

TOM: So rather than worry about running out of gas, Floyd, you should worry about whether your fuel filter is clean. Changing it frequently is your best defense against clogged injectors. We suggest you change it even more often than your owner's manual recommends (once a year is just about right). Filters are much cheaper than injectors, so they're a cheap form of insurance. (Even cheaper than that stuff Ed McMahon sells!)

RAY: So while we generally recommend to our readers that they try not to run out of gas, we'll leave it up to you, Floyd. If you have a clean fuel filter, you can run out of gas as often as you like.

Dear Tom and Ray:

I have a 1979 four-cylinder Mustang. After I've been driving for 30 to 40 minutes, I hear a "grinding" sound when I accelerate. When this happens, I also smell something burning. Help! - Gilda

TOM: Gee, Gilda, it could be any number of things. The first one that comes to mind is that your car is overheating. When your engine overheats, it pings like crazy, especially during acceleration. Even though you describe the noise as "grinding," what you hear could be loud pinging (also known as "knocking").

RAY: The burning smell could also be related to overheating. If you've been leaking oil from the valve cover (which is very common with these engines), the oil - which has dripped onto the engine - could heat up and smoke when the engine gets hot.

TOM: At the risk of sounding forward, Gilda, I'd have to say that it's about time you got this sled to a mechanic. Loud grinding noises and burning smells are not symptoms about which one should sit down and compose a letter. These are calls to action. If your house were on fire, you wouldn't sit down and write a letter to the fire department, would you?

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