How accurate is your fuel computer? And how about the fuel gauge? And how did you decide it was good or bad. Ours seems pretty poor. Yesterday, the gauge was showing just over 1/4 tank remaining. I put in 14.1 gallons. That leaves 9 gallons of a 23 gallon tank. Certainly much more than 1/4 tank. Fuel range was indicating 87 miles to empty. after refueling it showed a range of 287 mile all the while showing average fuel economy of just over 16. That doesn't add up. 100 mile later it was showing about 16.7 mpg, and still showing 265 miles remaining? I have a new Honda Africa Twin (Adventure motorcycle) its computer appears very accurate. 98 Grand Cherokee, its spot on accurate, 95 Grand Cherokee very accurate. So what's the story with the GX. This car has ~ 6000 miles on the clock. Wife's driver, so I have not had the opportunity to notice it until now.

 

Couple of things to keep in mind: 1) Fuel gun may have sensitive trigger that may stop fueling that give you a false indication of topped off already. It also affected by the gun position and how it has been inserted. You can always try pull a little out when the pump stoped and try again to see if it is actually full; 2) the Distance to empty display is calculated based on LAST instant sample of fuel consumption. I think the Lexus is calculate in every two minutes (i couldn't recall in exactly). So, your last two minutes of driving condition could be totally different than your entire trip, which could give you the wrong idea. With fairly stable driving condition, I found the reference with my GX is pretty accurate.

 

I expected it to be pretty accurate, but doesn't seem to be. I made sure the tank was full when I got gas. I expected that it shut off early, but that was not the case. And after fueling the gauge showed full. And stayed on the full mark for probably25 miles, as I would expect before coming off the peg. I expected the "Distance to empty" would be calculated on the current average mpg that the computer senses. But unless my math is off, or I'm missing something its, it's way off. Even the gauge seems way off. I'm going to keep an eye on it. See if maybe its just a fluke. We stopped for gas, even though I thought we should have had plenty for the rest of the trip, based on that gauge.

 

 

Since its my wife's driver, it doesn't get calculated very often. I always calculate it when I'm using a vehicle. That's why we haven't noticed it before. I need to check it a bit and see if its just a fluke. The gas gauge accuracy is also in question. It was probably almost a needle width above 1/4 tank when I got gas. I expected to put in maybe 16 or 17 gallons. But only put in 14. When I did, the miles remaining to empty came up, but not to what I expected. I'll watch it for a while and see what happens.

 

My cruise distance was at 0 miles this week, I drove it another 15-20 miles.

My fuel gauge isn't very accurate. It goes from 1/4 tank to empty very quickly, and goes from full to 3/4 very slowly.

 

That is kind of normal way how it was set. Because when it's full, the needle won't take off from (beyond the F marker) after about 20 miles. And E mark is where roughly you would have at least 5 gal in the tank. There is a also a reserve area of about 1.3 gal at the bottom of the tank area. So, when it's near true empty, the needle will be far below the E marker. So the gauge itself is not exactly liner as it marked. It provides some safety into the design if you were completely rely on the gauge as references.

 

Yep, messed up my salvation “Cussin” on Sunday when this 6lb behemoth quit whilst turning up a hill. The cluster showed 13 miles to empty and no low fuel indicator was on. She quit right there on the spot and thankfully the gas station was right on the other side of the hill. I casually costed into the pump area (doing my best to be cool and not look out of the ordinary, especially in the hood). LX is at Lexus now, hoping for a good and cheap report.