'93 Sentra is suppose to have 35mpg, but i only get 31mpg

[mithrandir2001]

Ever since they switched to winter-blend gasoline here, the fuel economy on 10K mile Accord dropped by almost 2mpg. :Q I think we finally switch back to the normal stuff on 3/31. So you have to wonder...are the anti-smog additives worth the fuel economy loss? I think not.

 

[JEDI]

<< do you keep your air condition on all the time? also if you floor it alot, that would suck huge amount of gas. it all depends on your driving style.

when i see a red light far away, i dont step on the gas so i can get to the stoplight faster and wait for it to turn green. i let my car roll off the momentum and by the time i get there the light already turned green. unnecessary breaking causes unnecessary accleration which gets you bad milege. >>



yep, that's what i do. pisses off the people in back of me

 

[beat mania]

Try drafting one of those big ass 18 wheelers for great mileage.

 

[Evadman]

Bah, I get just over 5 MPG. I don't want to hear it.

 

[JEDI]

ok, the car is a '93 sentra. i bought it in '96 w/36k miles. even in 1996, i was only getting 31mpg. (yes, i'm happy that at 200k miles, it's still 31mpg).

but was asking why in 1996 (3 years after the car was made and 36k miles) it's giving me 4mpg less??

 

[TuffGuy]

<< ok, the car is a '93 sentra. i bought it in '96 w/36k miles. even in 1996, i was only getting 31mpg. (yes, i'm happy that at 200k miles, it's still 31mpg).

but was asking why in 1996 (3 years after the car was made and 36k miles) it's giving me 4mpg less?? >>


because the 35mpg is at the LIGHTEST throttle. if you accelerate faster than the minimum needed for it to get into the next gear, that figure will drop.

btw, my eclipse gt, which is rated at 20-28mpg gets 25-29mpg. which makes me happy.

 

[Cyberian]

<< They do everything humanly possible to inflate the MPG number. They optimize what speed they travel at - usually around 55 is ideal for low gas consumption. They probably used a manual transmission car. They accellerate very carefully as to conserve gas. They take out all the weight possible from the car (why do you think spare tires are so small? it pushes the MPG up!). No luggage or anything of the kind. They use a newly tuned car.

So 35 MPG is not under "normal" circumstances. They don't really cheat it, but they do everything possible to "help themselves out." >>

Are cars still actually tested on the road?
I thought they used a dynamometer-like contraption to put the cars on and run them through a city/highway test.

Oh yeah, aren't the tests conducted by the EPA? Why would they want to inflate the MPG figures?

 

[Zenmervolt]

<< Try drafting one of those big ass 18 wheelers for great mileage. >>

Hoping this is sarcasm, but just in case I'll deal with it. Drafting is a phenomenon which only becomes useful at speeds above 75 mph and requires that the vehicles be extremely close. If you are more than 2-3 feet from the back of a semi trailer, you are in the wake turbulance which will cause MORE drag and will make fuel economy WORSE. You can test this with a car that has a removable sunroof. With the sunroof removed (or completely retracted), drive with the lane ahead of you clear; you will notice that the airflow is smooth. Drive behind another vehicle; you will notice that there is significant buffetting and the airflow is anything but smooth. Turbulant airflow causes drag. Unless you're stupid enough to ride 2-3 feet behind a semi at 75+ mph (which is just asking to get decapitated when the semi stops and you don't), there is only detrimental effect to fuel economy by riding behind a semi. Not to mention the fact that you are probably really pissing off the driver of a 40+ ton rig by driving in his blind spot.

ZV

 

[JEDI]

i havent changed the spark plug wires at all in the 200k miles. do i need to change it since the gas milage is the same as at 36k miles?

 

[Angrymarshmello]

nm read it wrong

 

[Thegonagle]

<< i havent changed the spark plug wires at all in the 200k miles. do i need to change it since the gas milage is the same as at 36k miles? >>

No. Wires are wires. They conduct electricity. You shouldn't need to replace them unless the insulation is starting to go, in which case your car would run crappy in moist/dewy/rainy conditions.

Now I?m wondering if your O2 sensor could have been dead all this time. Hmmn.

 

[Jerboy]

<< Here's my story:

in 1996, i bought a '93 sentra w/36k miles on it. the specs say 35mpg highway. i only get 31mpg. In the owner's manual, i found the orginal paper that dealers stick on the windshield to show how many mpg a car gives. it says 35mpg highway.

but i only got 31 mpg on highway (connecticut to dc round trips, no traffic). Just wondering what could be robbing me of the 4mpg??? >>




It's not that unusual. Cars seldom get the rated mileage. The manufacture's definition of city driving is your usual driving and highway driving is driving 45 or 55 on straight path without slowing whatsoever.

They usually warm up the car ahead of the time and fuel flow meter is started only after the engine is warmed up.

 

[ElFenix]

the EPA defines the test used to determine MPG, not the maker. its still pretty ideal.

 

[goodoptics]

<< i havent changed the spark plug wires at all in the 200k miles. do i need to change it since the gas milage is the same as at 36k miles? >>



I would leave it alone as long as it is still in good condition.

 

[JEDI]

Garfang, why do u think my O2 sensor is dead?! and if it's dead, how can i pass emmissions??

and how can i tell if there's a problem w/the O2 sensor?