Moderator: volvite
That's exactly what my '08 4.0 4WD gets with normal driving around my smallish town (50+% towing 4500#) using 87 octane gas. The EPA sticker said 14 mpg City and those ratings are usually optimistic.ice4x4 wrote:Yeah i have been driving very softly on the pedal and using cruise control as much as I can. If im only getting 19l/100km thats only 12.3mpg.
So something is not right...
be very careful when cleaning the MAF.ice4x4 wrote:Thanks for the tips,
I bought some new spark plugs today along with some injector cleaner, MAF sensor cleaner and throttle body cleaner. Will give those a go and see how I get on.
I did notice in the service record the spark plug service was missed, the car has 190000km's on it so if they are the original plugs then they are way overdue.
The upstream O2 sensors are referred to as A/F Sensor 1 in the Pathfinder Service manual, correct?TooTallMike wrote:Up stream O2 sensors can be the culprit. Mine was getting 17mpg easily and then it dropped to 13mpg. Connected my obd 2 and used torque lite and saw one of my upstream sensors had voltage way outside its normal zone so it was reading lean and was dumping fuel to compensate for the false reading. Replaced it through Rock Auto and it's been good to go ever since. Also your plugs should make a difference since they skipped the last go around. Good luck and I hope you get it fixed!
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Since Courtesy Nissan lists the sensors at over $200 ea. I just want to make sure I'm getting the right part.MIXTURE RATIO FEEDBACK CONTROL (CLOSED LOOP CONTROL)
The mixture ratio feedback system provides the best air-fuel mixture ratio for driveability and emission control. The three way catalyst (manifold) can then better reduce CO, HC and NOx emissions. This system uses air
fuel ratio (A/F) sensor 1 in the exhaust manifold to monitor whether the engine operation is rich or lean. The ECM adjusts the injection pulse width according to the sensor voltage signal. For more information about air
fuel ratio (A/F) sensor 1, refer to EC-142. This maintains the mixture ratio within the range of stoichiometric (ideal air-fuel mixture).
This stage is referred to as the closed loop control condition.
Heated oxygen sensor 2 is located downstream of the three way catalyst (manifold). Even if the switching characteristics of air fuel ratio (A/F) sensor 1 shift, the air-fuel ratio is controlled to stoichiometric by the signal
from heated oxygen sensor 2.
The OEM sensors for Nissan are made by NTK and you can get them a lot cheaper at Rockauto.com compared to the dealer part.ssobol wrote:As I read the manual for the 4L engine, the A/F sensor is upstream and the O2 sensor is downstream.
The A/F sensor is changed via access behind the wheel well liners and the O2 sensors are on the exhaust tubes underneath.
From my service manual.
Since Courtesy Nissan lists the sensors at over $200 ea. I just want to make sure I'm getting the right part.MIXTURE RATIO FEEDBACK CONTROL (CLOSED LOOP CONTROL)
The mixture ratio feedback system provides the best air-fuel mixture ratio for driveability and emission control. The three way catalyst (manifold) can then better reduce CO, HC and NOx emissions. This system uses air
fuel ratio (A/F) sensor 1 in the exhaust manifold to monitor whether the engine operation is rich or lean. The ECM adjusts the injection pulse width according to the sensor voltage signal. For more information about air
fuel ratio (A/F) sensor 1, refer to EC-142. This maintains the mixture ratio within the range of stoichiometric (ideal air-fuel mixture).
This stage is referred to as the closed loop control condition.
Heated oxygen sensor 2 is located downstream of the three way catalyst (manifold). Even if the switching characteristics of air fuel ratio (A/F) sensor 1 shift, the air-fuel ratio is controlled to stoichiometric by the signal
from heated oxygen sensor 2.
I did this recently on a Toyota van I have, the part was $197, but there is only one of them.