Anyone own a G35 with over 100k miles?

[pintsize725]

What is the best/worst MPG you are getting?

[zozoka1212]

Telco and toolboothwilley for sure. Maybe some others.

Just wait they'll be here soon.

[telcoman]

What is the best/worst MPG you are getting?

My best MPG was in April 08 between Va and Georgia where I got 27.9 MPGThe worst was 16.5 with the wife using my G in Florida for short 2 mile trips.My current MPG is in my signature.My MPG will improve as the NJ weather warms up.My G does not like very cold, very hot, or very humid weather which is why I got my best mileage driving to Florida in AprilI also did a study using 87, 91, and 93 octane for a 1 month period for each grade.The study proved to me without a shadow of a doubt that regular is just fine. Many here do not agree as they are more performance oriented but I commute 100mi/day and my G runs just fine.

My plugs at 106.7k miles



Telcoman

[pintsize725]

Ok I am averaging 12-14 mpg right now. I would appreciate help figuring out what I can do to improve this. I just changed my spark plugs last night (Ngk-Ix-Iridium), dealership tag says oil change not due til 112k miles, tires are inflated to 30psi, running a tank of gas with fuel additive (not even sure if this recommended). I use only 93 octane fuel and my commute to and from work is 18 miles in each direction. Of those 18, maybe 4 are spent going through two lights, the rest is all highway which I cruise at 74 mph.

Currently I have to put gas about every 3-4 days. I have only run down the tank to about 1/4 before filling up.

<<< As my info there says, I am still learning, never owned an Infiniti before.

[telcoman]

Ok I am averaging 12-14 mpg right now. I would appreciate help figuring out what I can do to improve this. I just changed my spark plugs last night (Ngk-Ix-Iridium), dealership tag says oil change not due til 112k miles, tires are inflated to 30psi, running a tank of gas with fuel additive (not even sure if this recommended). I use only 93 octane fuel and my commute to and from work is 18 miles in each direction. Of those 18, maybe 4 are spent going through two lights, the rest is all highway which I cruise at 74 mph.

Currently I have to put gas about every 3-4 days. I have only run down the tank to about 1/4 before filling up.

<<< As my info there says, I am still learning, never owned an Infiniti before.

Texas is a big state. Have you ever done any 300+ mile trips?18 miles barely gets the vehicle up to operating temperature.G's do not like short trips. You will get your best mileage at 70-75 MPH on cruise control for a few hours.My tires are 38lbs when cold

Here are my test results on using premium vs regular

[pintsize725]

No, I have yet to take it on a huge trip. Seems I'm doomed to low mpg.

[Focusedintntions]

Yeah first step to getting better gas mileage is to up the tire pressure..30psi is way to low. You should be using like 36-40 ps when cold. I run 42psi cold in my tires. Max for my tires is 55psi. Check what the max is of your tires and go with a safe limit below it.

[Focusedintntions]

Also I average about 20-22mpg with mixed city/highway driving. My best tank was a on a drive to PA where I average 26 mpg. On my last long trip to GA with a fully loaded car i got an average of 24.8 mpg

[gwoods]

Ok I am averaging 12-14 mpg right now. I would appreciate help figuring out what I can do to improve this. I just changed my spark plugs last night (Ngk-Ix-Iridium), dealership tag says oil change not due til 112k miles, tires are inflated to 30psi, running a tank of gas with fuel additive (not even sure if this recommended). I use only 93 octane fuel and my commute to and from work is 18 miles in each direction. Of those 18, maybe 4 are spent going through two lights, the rest is all highway which I cruise at 74 mph.

Currently I have to put gas about every 3-4 days. I have only run down the tank to about 1/4 before filling up.

<<< As my info there says, I am still learning, never owned an Infiniti before.

How did the plugs look?

I have 73k miles on my G and beat on it hard everyday. I average 19 mpg in town. On a trip North I got 26 mpg driving the speed limit and using the cruise control. I had someone following me so I had to slow down.

[quixote]

My reading is 46,000 miles now. I think I got 16mpg for the city driving in Boston.

[pintsize725]

My plugs looked just a tad worse than Telcoman's above.

For note, the first time I filled the tank after buying it, the gas pump clicked at 3/4 of a tank. The second time, no clicks until absolutely full. Third time (yesterday) husband said it clicked and he looked at fuel gage. It showed on the Full line, but after 15.9 miles, it was already almost down to 3/4 of a tank. Isn't this one of the recall issues? He also said it clicked after 7.xx gallons and that he figured my mpg to around 22.

Honestly I would take it back to the dealer but I am broke for a few weeks due to a vacation coming up.

Any ideas?

[gwoods]

replacing the sending unit in the tank should fix that. Its not too difficult, drain tank. lower tank, remove giant plastic collar from sending unit remove and replace with new sending unit.

Sending units are $200-$300 normally for the part and it will take about 5 hours.

As a bonus you will get a new pump and filter! which probably need to be replaced anyway.

[pintsize725]

So I took a few pictures of my car today. Is this normal?

Before my ride home from work and after filling up last night.



After my ride home from work.

[TinsleyC]

Maybe it's leaking out? Do you smell gas? Try resetting your MPG meter when you're on the highway at crusing speed. What do you get over a 5-10 mile stretch? Are you up and down mountains?

[pintsize725]

No, I do not smell gas from anywhere in the car or outside. I don't think I have an mpg meter, isn't that only for cars with nav? No mountains (central Texas), just small hills here and there like on ramps.

[SoCalSideways]

i am not the best economic driver but i still get 17 mpg in the city alone. i suggest you have a mechanic check it up for you man. not normal.

[telcoman]

So I took a few pictures of my car today. Is this normal?

Before my ride home from work and after filling up last night.



After my ride home from work.

With the gas gauge needle square on the 3/4 mark I've usually traveled 120 miles since the fillup and restting odometer A to zeroAt the 1/2 mark square on I've usually gotten 220 to 230 miles and at the 1/4 mark 300 to 350 miles.

Telcoman

[pintsize725]

With the gas gauge needle square on the 3/4 mark I've usually traveled 120 miles since the fillup and restting odometer A to zeroAt the 1/2 mark square on I've usually gotten 220 to 230 miles and at the 1/4 mark 300 to 350 miles.

Telcoman

So these readings are horrible then?

I really don't know if I can take it to the dealership where I bought it (not Infiniti). They had me buy a special warranty for the car but honestly I wasn't given all the details. If you all can agree that I've done everything I can without taking it in then, I'll have to see what other options are.

[tollboothwilley]

What is the best/worst MPG you are getting?

152K + miles right now...

Got every mod in the books that I can bolt on pretty much.

Last 100% HWY driving I averaged 28.7 MPG

70% City/30% HWY mix generally gives me around 20-21 MPG

All city is around 19 MPG

I think the worst fuel economy I've ever had was around 17 MPG - lots of stops/starts letting the car warm up for a while and racing everywhere I went.

Normal driving I'm at 80 miles at the 3/4 mark, 150 miles at 1/2, 230 miles at 1/4.

HWY driving I'm at 120 miles at 3/4 mark, 250 miles at 1/2, 350 miles at 1/4.

[tollboothwilley]

There is a recall for the 2003 but was was due to gas tank filler neck. They just replace it. You should call an infiniti dealership and give them your VIN #. Have them check and see if there are any outstanding recalls for your vehicle.

It is possible that you are getting decent gas mileage but your fuel tank never gets completely full (float going bad...). You need to drive 50 miles from a full tank and then refill it with gas. Divide Gallons added by miles driven. That will give you a true reading of MPG.

That said, you are not the first person to deal with bad gas mileage woes if that is the case.

Tire pressure should be at least 35, I keep mine around 38 PSI when cold.Clean MAF.Clean Air Filter/replace.Plenum spacer to make you happy and it improved my MPG when i wasn't stomping on it.

You could have a small gas leak that you don't know about. If there is one it would likely be in the evap system.

[pintsize725]

Thanks everyone for all the suggestions/info. I will be taking it to my mechanic to check all these things. Just aired up my tires as well to help me get down there.

Also called Infiniti and there are no outstanding recall issues for the VIN.

[gwoods]

There is a recall for the 2003 but was was due to gas tank filler neck. They just replace it. You should call an infiniti dealership and give them your VIN #. Have them check and see if there are any outstanding recalls for your vehicle.

It is possible that you are getting decent gas mileage but your fuel tank never gets completely full (float going bad...). You need to drive 50 miles from a full tank and then refill it with gas. Divide Gallons added by miles driven. That will give you a true reading of MPG.

You could have a small gas leak that you don't know about. If there is one it would likely be in the evap system.

That is good advise! When the pump clicks off try to put more gas in until you spill some. Then drive 50 miles without turning off the car and stop at another gas station and fill it up again until gas spills out the filler.

Divide the miles by the gallons and see how you are doing.

If the filler neck is leaking the gas would evaporate you would not see a puddle of fuel under the car it would just go out into the air. Do you smell a strong gas odor at the back of the car?

[pintsize725]

That is good advise! When the pump clicks off try to put more gas in until you spill some. Then drive 50 miles without turning off the car and stop at another gas station and fill it up again until gas spills out the filler.

Divide the miles by the gallons and see how you are doing.

If the filler neck is leaking the gas would evaporate you would not see a puddle of fuel under the car it would just go out into the air. Do you smell a strong gas odor at the back of the car?

Thanks, I will try it Friday. No, I have not noticed a gas smell at all. For an update, this is the same tank of gas after driving today. Did no driving Tuesday.

[Father_Flanagan]

Telcoman:

It is great to see someone else out there with the same problem as me. My wife swore I was crazy, with all of my gas logs, until I showed her your post. Now she might finally give me a break! Thanks for sharing your affliction.

[gwoods]

Telcoman:

It is great to see someone else out there with the same problem as me. My wife swore I was crazy, with all of my gas logs, until I showed her your post. Now she might finally give me a break! Thanks for sharing your affliction.

Two crazy guys with the same hang ups doesn't make either of them sane

[telcoman]

Telcoman:

It is great to see someone else out there with the same problem as me. My wife swore I was crazy, with all of my gas logs, until I showed her your post. Now she might finally give me a break! Thanks for sharing your affliction.

Telcoman:

Now she might finally give me a break! Thanks for sharing your affliction.

Don't count on it

I still have them for cars I no longer own. She wants me to throw them out

I've always kept logs of MPG, oil changes,and all vehicle expenses.
Modified by telcoman at 2:52 PM 2/25/2010

[pintsize725]

Filled up today when tank was down to what gauge showed 1/4 tank. Filled up with 12.808 gallons. Mileage on trip was 231.90. This means my mpg was 18.1058ish. Correct?

[kmckis1029]

152K + miles right now...

Got every mod in the books that I can bolt on pretty much.

Last 100% HWY driving I averaged 28.7 MPG

70% City/30% HWY mix generally gives me around 20-21 MPG

All city is around 19 MPG

I think the worst fuel economy I've ever had was around 17 MPG - lots of stops/starts letting the car warm up for a while and racing everywhere I went.

Normal driving I'm at 80 miles at the 3/4 mark, 150 miles at 1/2, 230 miles at 1/4.

HWY driving I'm at 120 miles at 3/4 mark, 250 miles at 1/2, 350 miles at 1/4.

+1 my gas milage closely follows this... as long as im not using shells new nitrogen enriched gas... i was using it for a month and kept wondering why my gas milage was sucking... then one day the power was out at the shell station usually go to... so i had to get BP gas... and my milage shot up back to normal... i was like WTF!!!

my 2005 G35x seems to like BP or Chevron... my point is change gas brands and see what happens...

[pintsize725]

Well s***, I just filled up at Shell. Maybe next tank will be Chevron

[telcoman]

Well s***, I just filled up at Shell. Maybe next tank will be Chevron

I use WaWa as they are usually the cheapest.