'07 3.5L poor mph or kpl

[TyH]

Hey guys!

Well...I'm a new Altima owner and I can definitely thank this board to helping me make the right choice! I've always loved the VQ engine ever since I took a friends fresh off the lot '03 350 many years ago!!!

Though I'm new to the board, I'm not new to forums or the search function. LoL. Though I've a question that seems hard to find info on...

I bought my Alti from a certified dealer, presumably they would have done their full "million point inspection" properly. Which would have included a basic tune up...

Here's my issue...I'm getting roughly 19 L/100km (12 mpg) in the city. I understand there's many factors like tire pressure, playing the red light racer and so on. I've checked my pressure and Ive let the CVT gently cruise around at 50-60km/h. Even with monitoring my speed and acceleration I'm still getting less mpg than a Hummer lol!

Has anyone else experienced this? If so...what did you do to correct the issue?

If not...maybe I'm wrong and Nissans 20mpg (city) was an over estimate?

Thanks in advance! I look forward to years of insight fro this group!
Modified by TyH at 9:51 AM 2/17/2010

[TyH]

So the only advice I've been able to find is #1 possibly a dirty MAF which is causing it to run rich or #2 disconnect the battery to reset any mis readings it may have stored.

Well...I tried disconnecting the battery for 20 mins or so, then I took the car out for a nice, snowy afternoon spin. It seems to have worked; after 13.1 km's it averaged 12.3 L/100KM (roughly 19 MPG). I tried not to accelerate too hard, but I didn't want to skew the results either so I tried to even things out.

If anyone still has any thoughts/suggestions/input/stories to share, it would greatly help!

[TyH]

Well...the problem came back! Luckily the check engine light came on which turned out to be a slow O2 sensor. The slow sensor would explain why the car was running rich AND has very poor milage!

My only question, is this normal for a '07 with just over 70km?

Regardless, I hope this helps anyone that may have poor mileage but the check engine light hasn't popped on .