[cschmidt]

Folks,

I did a search and saw a reference to this but no solution offered.. I don't get to drive our Mo often, SWMBO ( She who must be obeyed) and the kids get it. Our drive way slants so the passenger side is lower when parked, level front to back. I get in tonight and the fuel gauge is at E and the DTE is **. My wife says, it's not empty it does that all the time. She had set the trip odometer after filling up and it was at 320. We usually get just under 400 miles on a tank with a fillup at 18-19 gallons.

So we start driving. Around a few corners, up a hill, then 2 miles down a flat road. The fuel guage is slowly climbing, DTE still **. We hit a bump ( or co-incidence I looked then) and the DTE jumps to 50, then up to 68 in a few more seconds.

First question.. has anyone else seen the fuel gauge act like this? Is there a baffle in the tank that will cause this or is this likely a sticky sensor?

Second question.. the DTE has been discussed and found not to be accurate. Is there an average amount of fuel left when the low fuel light comes on?

Thanks, SWMBO runs the gas low all the time and I would like to understand what guage to trust.

Chuck

 

[zebelkhan]

Don't trust either gage as their calibration can change over time. Also, over time sluge accumulates at the bottom the tank which mixes with low levels of fuel and can eventually plug your filter.

IMO, it is a good idea fill-up the tank when it reaches 1/4 full. The gage for last 1/4 tank dropps very rapidly and cannot be trusted. It is not a good situation when you run out of gas with kids in the car!

On a couple of occasions when I had no access to a gas station and the light came on, I had about 2 gallons of gas left. When DTE shows "*", I had 1.5 or less gallons of gas left.

 

[cschmidt]

gas guage response?

OK, so I can understand the lack of accuracy on the DTE sensor and the low fuel light... but the gas guage? Again - I'm wondering if the sensor is sticking or is the fuel stuck on the wrong side of a baffle and just taking time to go back where the sensor is? It was probably at least 5 minutes and not until a bump that the guage starting coming back up from empty.

Still puzzled.

Chuck

 

[Gonzo]

One thing to remember, the gas moves around a bit, so in calculating the DTE they filter the calcuations and don't update it frequently.

The other item is throttle position. Gas millege is greatly effected by this and as it tank drops this is more noticeable.

It goes with out saying that you most accurate reading is at a constant speed at a constand throttle position, i.e. moving on highway.

In my experice I have had the fuel light come on with 2-3 gallons of fuel remaining.

 

[Eric L.]

I've found there is around 2.5-3.0 gallons left when the low gas light comes on. I don't really give the DTE much attention, except during trips, when its kind of fun to see if I can make it go above 500 (i.e. just the number, actual miles to the tank always varies). Since the DTE is "set" from the mileage of your previous tank (or if you disconnect the battery, it will reset to some factory number, but quickly decrease afterwards), I need to be on a long trip where I get good mileage before the DTE will break 500. I've gotten it as high as 515 before, but thats because I got ~23.5 mpg on the previous tank of gas! This number of course, remains on the display for about 1 second before it drops to a more reasonable 425-450 range (for a long trip). In the city, my DTE display is usually around 300 miles whenever I fill up, and that makes sense since I get around 15-16mpg in the city.

I've never run it down to the * before, but it generally isn't a good idea to run the tank too low since the fuel pump itself uses the gasoline as both a lubricant and a coolant. Too little fuel in the tank could cause the pump to work harder (picking up the last bits on the bottom) and hotter.

 

[cschmidt]

fuel gugae reaction time

Folks,

The hidden question in my second post is the fuel guage. When parked on the hill and started it is dead zero "E". I go up the driveway, 1/2 mile to the main road, still "E". Then 2 miles down the road it slowly starts climbing ( and then the DTE reading goes from * to 10 to.... 68). This is about 5 minutes. I can fill a whole gas tank in 5 minutes and the guage will read full. To me it sounds like a sticky sensor.... Is there some crazy baffle inside that might cause this?

It drives me crazy because I don't let cars go that low, but SWMBO is the primary driver and gets it low all the time. She is used to her previous Lincoln Mark VIII that the fuel sensor and dte were very accurate. There must have been 3 times in the last month I hopped into the Mo and ready to go, but shut it off thinking it was dead empty.

Chuck

 

[MightyMo]

The fuel gauge reading is intentionally damped so you don't see it change when going over bumps or driving on inclines and such. You shouldn't expect it to correct completely the second you unpark from the slope.

The ambient temp gauge works the same way, it's only allowed to change by like 1 degree a minute unless you turn the car off and then back on and then it'll jump up. If you drive, and then park with the engine running, it'll slowly creep up even though it's heatsoaking like mad, then just turn the car off and back on and you'll see it leap up.

 

[cinergi]

I don't know the answer but I'd be curious to know if your Murano still does this after backing the car in (to reverse the slant direction).