I was driving my 05 Pathfinder on the interstate yesterday with cruise set at 60 and the AC on. Out of curiosity, I reset the miles per gallon calculation of the trip computer to find that it was registering some fairly high figures. I let it average for about 10 miles and it settled between 32 and 34 MPG. My initial conclusion was that this trip must be mostly downhill, so I figured, I'll see what happens on the way back later that night. To my suprise, I continued to run between 29-34MPG, so long as cruise was set between 60-65MPH. The 5MPH difference did seem to cost me a bit of fuel.
Today, I tested the truck on a 110 mile trip, starting at the same 60MPH and increasing my speed 5MPH about every 10 minutes. At 60MPH, I was still getting fuel economy in the 32-34 range. At 75 I saw a fairly large drop to around 25-26MPG, but still much better than the advertized 23MPG.
I did similar tests when the vehicle was much newer and never really topped out at much more than 21-23MPG. The truck now has about 10,500 miles on it and the weather is now a lot warmer than when I was originally testing.
Has anyone else noticed this sort of improvement as their Pathfinder aged and the engine was breaking in? Bear in mind, these tests were done on an open interstate with cruise set. If you vary the speed much, as in accellerate to pass another car, you definitely will not see the same results. That's likely why I haven't noticed this before, since I am always fighting rush hour traffic.
Last edited by kaedyn : Jul 1st, 2005 at 11:17 PM.
Reason: Typo
Is that just the computers average or did you figure it out when you filled the tank. I never trust computers in cars, because they are generally wrong, saying you got better mileage than the actual. It happens in the Saab also.
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'05 Pathfinder LE
'03 Saab 93SS
guys above what is the milage of your truck... i got 14 mpg max and my milage 1200 miles. do you think it will improve after a few thousand more miles.
At cruising speed, on a flat road, I can see you getting that kind of mileage. It is the getting up to speed and going up hills that bring the average mileage down.
the 26.3 MPG trip was done in last month and my Pathy had about 1000 miles at that time. The trip was about 200 miles one way which I got 26.3 mpg and on the way back, I got 25.2 MPG but the truck was fully-loaded. I used Shell regular (87).
Now I am using Premium to see if there is any difference. Also the computer in the Pathy is pretty accurate because I calculate the mileage by myself and it is within 0.5 MPG.
amazing for 1000 miles... do you have any simple mods like k and n filter etc... i usually use 93 octane if 87 is better i may just change to 87. tell me what happens when you use the premium gas.
Quote:
Originally Posted by patrick39
the 26.3 MPG trip was done in last month and my Pathy had about 1000 miles at that time. The trip was about 200 miles one way which I got 26.3 mpg and on the way back, I got 25.2 MPG but the truck was fully-loaded. I used Shell regular (87).
Now I am using Premium to see if there is any difference. Also the computer in the Pathy is pretty accurate because I calculate the mileage by myself and it is within 0.5 MPG.
I should clarify that this did include accelerating to 60+ and going up and down fair sized hills. Mileage would normally drop going up hill and raise going down hill for averages in the ranges I mentioned above. I didn't do much accelerating to pass anything, but did change lanes a bit. This was using premium fuel and I was using the trip computer for the average. I've always found it to be within about 0.5MPG of what I calculate myself.
I just found it a bit shocking that I was able to get that kind of mileage, since I've tried in the past and never had such luck. My previous 4 cylinder would get about 27-29 MPG at best on the highway.
Is that just the computers average or did you figure it out when you filled the tank. I never trust computers in cars, because they are generally wrong, saying you got better mileage than the actual. It happens in the Saab also.
I think you can trust this number. The trip computer uses information from the transmission to get the distance travelled. This would be the same as the odometer used for calculating mileage after a fillup.
The other number used for the mileage readout comes from the fuel injection system, which very precisely meters the fuel being squirted into the cylinders. This has to be accurate to a microscopic level.
One problem with calculating after a fillup is that there is no way of knowing that you filled it to exactly the same point each time. Like, how much gas did you "squeeze" in? Was the truck level each time? Is the gas station's pump accurate?
We have a car with a trip computer, and we have compared trip computer readings with fillup calculations, and I think the trip computer is accurate.
One output of trip computers that is not great is "Distance to Empty", or DTE. This is calcuated using the reading from the sensor for the fuel guage in the tank. As most people have noticed, the fuel guage does not go down in complete correspondence with the amount of gas used, and the DTE is only as accurate as that guage reading.
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'91 Pathfinder SE 5spd (now sold)
'06 Suzuki Grand Vitara JLX-L
amazing for 1000 miles... do you have any simple mods like k and n filter etc... i usually use 93 octane if 87 is better i may just change to 87. tell me what happens when you use the premium gas.
No mod., my Pathy is stock..... I just changed to premium last week, so I will monitor a few weeks and report back.
Today I took a 60 km (37.5 mile) round trip on highway and the mileage was 11.2 L / 100km (25.22 MPG), which was very good (considering Pathy is over 4500 lb and has a 4.0 L engine). The traffic was moderate and my speed was about 100-120 km/h (60-75 mph) with the AC on. The best I got was 11.0 L / 100km (25.68 MPG) when I exited the highway and the mileage jumped to 11.2 L /100km (25.22 MPG) when I got home with 4-5 complete stops.
-I have the 4x2 and i'm getting good numbers on flat surfaces and cruising at 60.
-I've noticed that 60 on the speedo is btw 57-58 on the computer... weird.
-The best I've gotten is 32 on a short, flat trip "Driving Miss Daisy" style.
-I have 12,000 miles.
-I always use Mobil1 5W30 Super Synthetic and follow a 5k OCI.
-I've noticed that I get better mileage with Exxon/Mobil gas???? It's curious... Cheveron/Texaco gives me mixed results as does Shell. I get terrible mileage with Sam's, Kroger, Conoco, and Citgo. I haven't used BP/Amoco much b/c there isn't one close to me.
-Before the truck was broken in, I drove 75 (on the speedo) from Nashville to Huntsville and averaged 21mpg.
And PLEASE note whether you're in the US or Canada. US gallons are 15% smaller than Canadian gallons, and so will give mileage figures 15% lower. Without this information, the data is pretty useless.
I wonder if the Nissan trip computers are calibrated for this?
I know that the trip computers included with the car we have, were all in US gallons, whether they were sold in Canada or the US. So we only use it in km/litre mode, and I have a conversion table for mpg.
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'91 Pathfinder SE 5spd (now sold)
'06 Suzuki Grand Vitara JLX-L
Linear Mode
