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A few odd issues

  #1  
Old 06-16-2015, 06:45 PM
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Default A few odd issues

I am new here having just bought a 2004 XLE in seeming exceptional condition. But there are few concerns with the computer.

1. Everything says it has a 18.5 gallon tank yet when the computer said I had 17 miles till empty, and the low fuel light was on, I filled up and it took 15.5 gallons.

2. The computer says I am averaging 25.6 MPG yet after filling it up it shows a range of 349 miles.

3. At 25. 6 and even 15.5 gallons it should show 395 miles

Any thoughts would be appreciated.
 
  #2  
Old 06-16-2015, 09:53 PM
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These systems are not precise. The density of the fuel varies, temperature of fuel in tank creates more or less vapor that gets sent to canister to burn later, filler on the pump stops at different times.
 
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Old 06-16-2015, 10:01 PM
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Originally Posted by toyomoho View Post
These systems are not precise. The density of the fuel varies, temperature of fuel in tank creates more or less vapor that gets sent to canister to burn later, filler on the pump stops at different times.


That may explain a "small" variance, but it can't explain an empty tank taking 3 gallons less than capacity.

Is the computer basically a rough guess then? I've never had the computer be off by any margins like that.

Is it possible to reset the computer? Would it accomplish anything?
 
  #4  
Old 06-16-2015, 10:27 PM
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Do you reset the average MPG when filling up?
 
  #5  
Old 06-16-2015, 10:32 PM
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Originally Posted by toyomoho View Post
Do you reset the average MPG when filling up?
This was the first fill up and yes I did.

I'm more concerned why everything says it has an 18.5 gallon tank and it reads empty when only 15.5 gallons can be put in. And why it is 35% off on range.
 
  #6  
Old 06-17-2015, 01:09 AM
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I would put a 5-gallon container full of fuel in my trunk, then run it until it really runs out of fuel.....see how far it went after the fuel light came on. Most car have at least a gallon left when the light comes on; most have 2 or 3 gallons left when the light comes on. Don't make it a practice to run out of fuel, though, because the fuel pump is lubricated and cooled by the fuel running thru it and will be damaged by repeatedly running the tank dry!
 
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Old 06-17-2015, 07:37 AM
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Originally Posted by mothorton View Post
I would put a 5-gallon container full of fuel in my trunk, then run it until it really runs out of fuel.....see how far it went after the fuel light came on. Most car have at least a gallon left when the light comes on; most have 2 or 3 gallons left when the light comes on. Don't make it a practice to run out of fuel, though, because the fuel pump is lubricated and cooled by the fuel running thru it and will be damaged by repeatedly running the tank dry!
Thanks

I thought about doing that but that will be a last resort as I have seen that cause many issues before as the last dregs of the crap laying in the bottom of the tank get sucked up and clog injectors.

I'd like to get some feedback from members here as to these questions.
1. Does this car actually have an 18.5 gallon tank
2. Does this car actually get 25MPG
3. Has anyone else had these issues with the computer being wildly off?
 
  #8  
Old 06-17-2015, 09:51 AM
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Spec states 18.5 gal tank.

MPG will depend on driving. Hwy driving for most tends to be around 29.

The fuel pump is picking up fuel at the same location regardless of how much fuel is in the tank. Issues of the picking up debris if the tank is low are not relevant.

As mothorton states the pump is lubed and cooled by fuel. For a longer life pump don't make a habit of running the tank until it is almost empty.

If wanting to determine average MPG, use trip meter and gallons used between fills. If done correctly over a number of fills the MPG obtained can be within a few tenths of a mile.
 
  #9  
Old 06-17-2015, 08:03 PM
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Originally Posted by toyomoho View Post
Spec states 18.5 gal tank.

MPG will depend on driving. Hwy driving for most tends to be around 29.

The fuel pump is picking up fuel at the same location regardless of how much fuel is in the tank. Issues of the picking up debris if the tank is low are not relevant.

As mothorton states the pump is lubed and cooled by fuel. For a longer life pump don't make a habit of running the tank until it is almost empty.

If wanting to determine average MPG, use trip meter and gallons used between fills. If done correctly over a number of fills the MPG obtained can be within a few tenths of a mile.
Thanks. I intend to monitor the MPG manually to see what it is really getting.

I called two Toyota dealers and I think they have a recorded response any time you mention the word mileage. But the bottom line is there is something waaaaaaay off. I am going to disconnect the battery and let everything reset and start from there.
 
  #10  
Old 06-18-2015, 10:33 AM
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Post back with your results.
 

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