What causes decrease in fuel efficiency?

[7391N]

I'm wondering what could be reasons for a car's decrease in fuel efficiency?

Before, my car (1997 Nissan Sunny/Sentra), runs an average of 350-360 kms from full tank (around 33 liters) to almost empty.

Now, it's only running up to 320-330 kms at full tank. I noticed the decrease after I went for the regular oil/ oil filter change.

Any ideas?

[roydok]

Poor driving habits and poor vehicle maintenance are some causes of decrease in ful efficiency.

[ghosthunter]

causes for decreased milage:

1. bad traffic conditions
2. tire pressure
3. wheel alignment
4. poor driving habits (sudden starts)
5. vehicle age & maintenance (leaks, tune-ups, etc)
6. car modifications for performance (wide tires, etc)
7. different quality of fuel

[7391N]

Thanks for the responses. Sa tingin ko "poor driving habits" ang problema

Anong pala ibig sabihin ng "sudden starts"? Yun ba yung pagpatakbo agad ng kotse after ma-start, without warming up? Kase ganon usually ginagawa ko, hindi ko na pinapa-idle pagka-start ko. Andar na agad after a few seconds lang. Is this an example of poor driving habits?

[66bunny]

Sudden starts—when the lights go green, hataw agad. Don't be heavy footed. Treat your accelerator pedal as if there's an egg underneath.

If you see a red light ahead, try to manuever the car with the slightest break or gas needed to go there. Let it cruise. Sometimes if you go to a full stop, the car needs a healthy amount of gas to move. So the trick is, slow down then if the lights turn green without you doing a full stop, the car need less gas to move.

As for the starting habit, no need to idle if your car is EFI. Drive right away. But don't go beyond 40kph during the first five minutes. Aircon should be off too. After that, you can drive faster and turn on the aircon.

And best of all, enjoy while you're at it.

[kiper]

7391N,

dapat nga masaya ka na sa 320-360 kms for 33 liters..

ako, 30 liters ko 150-180 kms lang..waah.. that's 5-6 km/L..huhu

ingat na lang sa pagdadrive..and follow the saving fuel tips..hehe

[7391N]

Originally posted by 66bunny
Sudden starts—when the lights go green, hataw agad. Don't be heavy footed. Treat your accelerator pedal as if there's an egg underneath.

If you see a red light ahead, try to manuever the car with the slightest break or gas needed to go there. Let it cruise. Sometimes if you go to a full stop, the car needs a healthy amount of gas to move. So the trick is, slow down then if the lights turn green without you doing a full stop, the car need less gas to move.

As for the starting habit, no need to idle if your car is EFI. Drive right away. But don't go beyond 40kph during the first five minutes. Aircon should be off too. After that, you can drive faster and turn on the aircon.

And best of all, enjoy while you're at it.

Ok so that's it. Hmmm, I admit I'm a bit heavy-footed. And I always turn on the aircon almost immediately after starting the car (followed by the stereo hehe). Thanks dude.

[7391N]

Originally posted by kiper
7391N,

dapat nga masaya ka na sa 320-360 kms for 33 liters..

ako, 30 liters ko 150-180 kms lang..waah.. that's 5-6 km/L..huhu

ingat na lang sa pagdadrive..and follow the saving fuel tips..hehe

Ano bang ride mo, kiper? Baka naman SUV sigurado akong gas guzzler talaga yung mga yon. Sa 'kin kase 1.3L lang ata yun kaya matipid sa gas, although lately nga 320-330 kms/33 liters (approx. 9.85km/liter) na lang.