i think my car is burning too much gas..

[iblingidawg]

i got an 04 g35 with about 17000 miles on it. I got a cold air intake on it. No check engine light on. In fact i just got the CAT fixed. Now i put about 42 dollars in the tank and i only got about 150 miles. I dont drive the car hard. I drive it normal by changing gears under less than 3k RPM. Is this normal on a G? Any thing i can do to improve gas mileage?

Thanks,

[telcoman]

i got an 04 g35 with about 17000 miles on it. I got a cold air intake on it. No check engine light on. In fact i just got the CAT fixed. Now i put about 42 dollars in the tank and i only got about 150 miles. I dont drive the car hard. I drive it normal by changing gears under less than 3k RPM. Is this normal on a G? Any thing i can do to improve gas mileage?

Thanks,

I filled mine up this morning. 362 miles it took 16.34 gallons. 22.15 MPG

How often do you change your air filter?What is the tire pressure in your 4 tires?Perhaps the wife has gained weight?

Telcoman

[joe603]

Why did you fix your CAT?? Sounds like an O2 sensor making it run rich. Get the dealer to take a look.

[iblingidawg]

The reason why i changed the CAT is b\c the check engine light was on and i when i went for inspection they failed me b\c of that. So they put a new one in.

Thanks, For input

[iblingidawg]

Do you think i should take this back to the DEALER?

[rn79870]

Researchers at the University of Illinois at Urbana-Champaign and Virginia Commonwealth University have concluded that the weight gain of Americans since 1960 has resulted in increased fuel consumption.

This is clearly a common sense conclusion - more weight in America's vehicles (and rear ends) means more fuel consumption - but this is the first study to attempt to quantify the impact of American's expanding girth on fuel consumption.

I think this is why my mileage is starting to suffer.

And yes, if you went 150 on 42 bucks. (14-15 gallons) then you've got a leak or a problem. I'd have a dealer look at it.

[iblingidawg]

I noticed that the filter i have on my cold air intake is a little dirty. Could that be the problem that is causing the great loss in MPG?

Thanks

[Jacko3]

iblingidawg:

I am a little confused, do you really drive the car at all? I have a 2007 G-35 Coupe, which I bought brand new, with more miles on it than yours. Are you really serious about not shifting beyond 3K? This could be the cause of the problem---less miles and too low RPM shifts ( I maybe wrong on this)

Do yourself a favor, take that car out for a spin, and flog the hell out if like your have never done before. I mean take the car up to 6500RPM consistently for about 45 minutes non stop. Before you do this, get a complete tune up. The car will not die. It will actually love you more each day and give you big kisses. The G-35 Coupe loves to be flogged. It hates to be babied. You will have more issues with the car babying it than when you really drive it.

After the tune and floggings, then go out and get the car moded out. Trust me, the mods do helo with gas mileage. My car is a rev up engine that gets somewher b/w 24 and 25 miles per gallon (estimated), except when I am flogging it.

Your car will die an early death if you don't drive it. And by the way, when i researched resale value with mielage and production year, it appeared that driving the car was more beneficial than not driving it, especially if yours is a 6MT.

Actually, this is the logic: If my car can survive flogging till 60K, then it probably is a good engine to begin with, and probably will last much longer, as long as I give it routine tune up. if the engine is a bad one, flogging the car will reveeal flaws beofre your warranty is up. Guess what? The dealership gets to fix it for free. So, what I have I got to loose? Absolutely nothing!

[iblingidawg]

honestly, i bought the car from a dealer in november 16K miles on it. I got it for 20k with bumper to bumper for 5 yrs. Now i just hit 17K. I have a cold air intake on it and now imthinking may it be that causing the loss of the gas mileage?

What else possibilities may it be?

Thanks, Andrew

[iblingidawg]

bump

[smockers83]

Well for one thing, you putting $42 in the tank tells us absolutely nothing. We need gallons, or a price/gallon to figure out how many gallons is worth $42. And we need to know how many gallons you used to get to 150 miles. If the gas you paid for was 3.20/gal, you ended up with about 12 MPG if you used every bit of the gas you bought. In city driving, you should be getting 17-18 MPG.

I can tell you now, its not your air filter. The car does not need to be flogged, especially at 6500 RPM for 45 minutes. There are some members on here who drive their G easily and have less problems than Jacko (sorry but its true buddy).

[telcoman]

Well for one thing, you putting $42 in the tank tells us absolutely nothing. We need gallons, or a price/gallon to figure out how many gallons is worth $42. And we need to know how many gallons you used to get to 150 miles. If the gas you paid for was 3.20/gal, you ended up with about 12 MPG if you used every bit of the gas you bought. In city driving, you should be getting 17-18 MPG.

I can tell you now, its not your air filter. The car does not need to be flogged, especially at 6500 RPM for 45 minutes. There are some members on here who drive their G easily and have less problems than Jacko (sorry but its true buddy).

When you fill up in NJ you need to get your butt out of your G. Stick your credit card in the pump & don't let those $ssholes at the gas station touch your G. I happen to use regular but use whatever makes you comfortable. When the pump clicks off, I usually round up to an even dollar or 1/2 dollar & sometimes it takes another 1/2 gallon.Try to fill up early in the morning on your way to work so you use up some gas to allow for expansion as the temperature rises during the day. Set your odometer to zero. Fill up again at the 1/4 tank mark & divide the gallons it took to fill up into the total miles traveled. This is the only accurate way to measure your MPG. After filling up your fuel gauge indicator should be resting just above the full mark.Mine rests exactly on the full mark after about 50 miles. When on the 1/4 mark mine takes 16 gallons. I filled my G earlier this morning. 343 miles traveled and it took 14.394 gallons (regular 87 octane). 343~14.394 = 23.6649 MPG which was slightly better than my previous 22.15 MPG earlier this week. I do a 100 miles per day commute on the NJ Turnpike & Garden State Parkway and cruise between 75 & 80 MPH. You do not need to abuse your G as some have suggested. (Sorry Jacko) I rarely shift over 4000 rpm & am very happy with mine. I change my air filter regularly and keep my tire pressure between 35 & 40lbs. There is a difference of a few MPG between a 6 speed manual and a 5AT. The G35X AWD gets even less MPG. My best MPG on a tank was 28.88 on a trip to Florida. If you are only using your G for short trips your MPG is going to be poor. Take it on a 3- 500 mile trip, put it on cruise control & compare?

Telcoman

[Jacko3]

iblingidawg:

My ride has over 18K plus, though engine is about 6K, and it rides just fine. No issues at all, except for the gas consumption because I flog it at least twice a day. This is a car to be enjoyed. But, I really think you should give your car a tune up, anyway.

[rn79870]

Is there a possibility someone "borrowed" a few gallons from you wothout you knowing it? IS your fuel door undamaged?

Also, do you let the car idle a lot?

Short in town trips with a cold engine?

Bad gas?