High gas consumption, O2 sensors?

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Rogue9
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High gas consumption, O2 sensors?

Postby Rogue9 » Thu Oct 26, 2017 5:00 pm

2010 pathfinder V6.

I've noticed that my Km's per tank have substantially dropped. 30-50km per tank.

No codes nothing unusual.
Plugged in my Bluetooth adaptor and torque app.
Both O2 sensors are reading majority 0.9v. Occasionally it drops down to .2 or .5 while driving but idle is constant 0.9.
Also when coasting it drops to 0 as it should when the engine stops fuel injection.

Are my O2 sensors old causing my truck to run rich? I have noticed the exhaust was a bit rich smelling.

Thanks I'm advance.


elementZ
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Postby elementZ » Thu Oct 26, 2017 8:40 pm

How much did the temp. drop? Colder weather means fuel mileage goes down.

Rogue9
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Postby Rogue9 » Fri Oct 27, 2017 8:01 am

It has never lost this much mileage in all the years I've had it. Even accounting for my auto starting which hasn't been much since it hasn't dropped below 0 yet.

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smj999smj
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Postby smj999smj » Fri Oct 27, 2017 6:21 pm

High O2 sensor voltage does indicate a rich condition. Make sure your thermostat is not stuck open and causing the vehicle to stay in open loop; if your coolant temp gauge needle is sitting much lower than halfway, then that's probably the cause. Otherwise, make sure your fuel pressure is not excessive and spark plugs are not worn out. It's possible that the front air/fuel ratio sensors ("oxygen sensors") could be operating inefficiently, but it would be odd that both went bad at the same time.

Rogue9
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Postby Rogue9 » Sat Oct 28, 2017 2:36 am

Well it's due for the first spark plug change next year. I guess I could move it up..... Thx

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smj999smj
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Postby smj999smj » Sat Oct 28, 2017 5:43 pm

If you don't have 105,000 miles on them yet, the spark plugs should be fine. 2010's came with the iridium plugs which usually don't get anywhere near worn until 120,000 miles.

Rogue9
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Postby Rogue9 » Sun Oct 29, 2017 12:42 pm

I think.... (sorry Canadian KM's here) I'm only at 88k miles.
according to torque, my fuel flow at idle is around 30cc/min.

coolant temp seems to climb and run normally. warms up and stays at 90 celsius give or take a couple.

AndrewT
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Postby AndrewT » Wed Nov 01, 2017 7:18 am

Sorry to hijack your thread, but what is the realistic MPG rating for these trucks? I get 15.5 mpg with mostly short distance driving with some highway, but I drive conservatively and don't mash on the throttle. The only way I can go above 16 mpg is if I get on the highway and cruise for 15 minutes or so.

Edit - truck as 115k miles on it, not too sure about the service history/spark plugs/etc.

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smj999smj
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Postby smj999smj » Wed Nov 01, 2017 9:37 am

AndrewT wrote:Sorry to hijack your thread, but what is the realistic MPG rating for these trucks? I get 15.5 mpg with mostly short distance driving with some highway, but I drive conservatively and don't mash on the throttle. The only way I can go above 16 mpg is if I get on the highway and cruise for 15 minutes or so.

Edit - truck as 115k miles on it, not too sure about the service history/spark plugs/etc.
Stock 4x4's usually get around 17-18 MPG combined and around 20-22 MPG on long highway runs. A lot of that depends on the driver; a light foot and using the cruise control tends to yield the best mileage. My 08 SE gets about 1-2 MPG better than my 06 LE on average.

Rogue9
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Location: Vancouver, Canada

Postby Rogue9 » Sun Jan 07, 2018 10:14 am

Still no change but I'm waiting till it warms up to do the plugs.
Maybe the throttle body and such needs a cleaning...
My average (according to computer) is 18L/100km, So 13MPG roughly.

Although for where I live (Vancouver, BC) this city isn't laid out well so to go 15km to work I have to cut through the city in traffic and up and over elevation to Sea level.
I'd say I drive fairly conservatively as well.
So each full tank I'd guess roughly I can pull 425-450 Km but I've noticed it drop to around 400 or less.


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