hi guys. can anyone help. I have noticed that in my G i am suddenly getting about half the miles to gallon that i used to. I haven't changed anything or changed the way i drive yet all of a sudden i am getting really bad mileage. anyone have any suggestions as things i should check? do you think an ecu reset would help? i am at a loss. cheers.

 

What's your MPG?? I'm getting an average of 18.1 and I do have a heavy foot at times.

 

i was getting 20 for over a year and now suddenly it drops to about 10 and that is if i am really careful!

 

i have a similar problem, my fuel mileage is somewhere near 16 mpg. i'm wondering if I have low economy because of the temperature...right now it is -20 degrees celcius or about -5 degrees fahrenheit. I also stomp on it everyonce and a while. I think I should get a fuel injector cleaning, could be helpful.

I'd like to hear some suggestions of maintenance etc. that would imporve fuel economy.

 

change your fuel filter and do you smell gas when you get out of your car?

- leaking fuel is 1 way you lose mileage
- fuel filter will eliminate your bad mpg. im pretty sure once you change that your mileage will be okay again.

i doubt its your fuel injectors because your car is 2003 ^

 

i havew been told that if you only use the car for very short journeys and in really cold weather, the milage will drop a lot! that is all i am doing at the moment so that seems to add up. i went for a longer drive yesterday when it was sunny and the mpg did appear to be better. will put in a filter and keep an eye on things. cheers

 

There's no way it will drop from 20mpg to 10 because of cold weather.

Whats your mileage on your vehicle? What year,model is it? What's been replaced?

Have to know that before people can start giving you suggestions.

 

There is no fuel filter to change. Everything is internal in the gas tank. There certainly is a problem if the change is that great. If there is no gas leak and the car is under warranty, take it to the dealer for a diagnostic check. Good luck.

 

^^ ohh really?

my bad, just got into g35 last week ahha.

im basing majority of my info from symptoms i have off my 240sx i sold recently to get a g35 woot woot.

 

Yes, i have experienced this same thing. Currently i'm getting 15-16 mpg. I warm up my car for 3-5 minutes before every drive, and all of my drives are 15 minutes or less, except everyonce and a while. I also step on it a decent amount. I'm expecting to get about 18-20 mpg, when i change out my air filter, and do a fuel injector cleaning, will let you know in a couple of weeks. when my car was on its last trip, doing about 65-70 mph, i was getting about 25 mpg

 

Do you live in an area where they Oxygenate the gas during the colder months? I do, and it usually drops me down 3-5mpg but not 10... stupid winter...I'm movin to SoCal! who's comin with me!?

 

sadly socal is out of the question for me... I live in London! nobody round here knows much about about these cars as not on sale here. I got mine as import from japan so is a skyline 350GT as apposed to a g35. Is a 2003 car with about 65000 miles on the clock. I have an injen CAI, a 5/8 plennum spacer and a full cat back dual exaust system, as well of countless other dress up parts. even with these changes was still getting 20mpg. it has a full service every spring. seems strange to suddenly be getting lower milage. it started as soon as the temperature dropped, cant all be a big coincidence surely??? i try to run the car on 99 ron fual, usually have to settle for 95 but did have to use some crap 95 recently just to get home, will that of made such a difference as that???

 

sorry that was try to get 99 ron, usually use 97 but had to use 95 once.

 

shouldn't make that much of a difference how much ron you put in there, obviously somewhat, but shouldn't be terribly noticeable, make sure you always get the best. I think the cold weather is what is eating away at the G. Whenever its above 5 degrees celcius or about 25 fahrenheit, my fuel economy is much better.

 

I seem to be eating through a unusually high amount of gas aswell. Out of 1/2 a tank, (~10 gal) I can usually get about 150-165 miles. Which rounds out to ~16 MPG. I don't drive my car too too hard, but probably average for a typical young G owner. I've read the suggestions above, anything else?? Mine is a 2003 w/ 39,8xx on the odo.