Notices
General Mustang Chat Not Tech or Model Year Specific

Gas gauge and digital gas gauge innaccurate

Old 10/2/12, 09:43 PM
  #1  
V6 Member
Thread Starter
 
Bushguts's Avatar
 
Join Date: September 9, 2012
Location: Charlotte nc
Posts: 94
Likes: 0
Received 0 Likes on 0 Posts
Gas gauge and digital gas gauge innaccurate

I have a little over 1k on my car. When it says I have 15 miles left I go and fill up and it takes 13 gallons. Why is it still off after this kind of mileage. And my gas needle is on E while this is happening. I can't judge how many miles I truly have left. This is a pain because I'm spending money too soon.

Does this happen to anyone else? If so what did you do to fix this? It's so annoying.
Bushguts is offline  
Old 10/2/12, 10:08 PM
  #2  
Shelby GT350 Member
 
watchdevil's Avatar
 
Join Date: February 5, 2008
Location: Chattanooga
Posts: 2,339
Likes: 0
Received 3 Likes on 3 Posts
Originally Posted by Bushguts View Post
I have a little over 1k on my car. When it says I have 15 miles left I go and fill up and it takes 13 gallons. Why is it still off after this kind of mileage. And my gas needle is on E while this is happening. I can't judge how many miles I truly have left. This is a pain because I'm spending money too soon.

Does this happen to anyone else? If so what did you do to fix this? It's so annoying.
It is very important to not let the fuel tank run dry or you will burn up the fuel pump or encourage possible sediment in the tank to stir up and clog the pump. Ford designs in the margin of error for idiots who insist on going as long as they can without filling up. The Mustang gives plenty of warning at 50 miles left, then at some point when it gets even lower it turns the fuel gauge bright red. I will often reach the 20 miles left mark. When I fill up it's almost always between $48-$50. Really you have nothing to complain about unless you just want to be stupid and burn up your fuel pump.

Last edited by watchdevil; 10/2/12 at 10:10 PM.
watchdevil is offline  
Old 10/2/12, 10:32 PM
  #3  
V6 Member
Thread Starter
 
Bushguts's Avatar
 
Join Date: September 9, 2012
Location: Charlotte nc
Posts: 94
Likes: 0
Received 0 Likes on 0 Posts
I'm not complaining. Just looking for accuracy.
Bushguts is offline  
Old 10/2/12, 10:39 PM
  #4  
Shelby GT350 Member
 
watchdevil's Avatar
 
Join Date: February 5, 2008
Location: Chattanooga
Posts: 2,339
Likes: 0
Received 3 Likes on 3 Posts
Originally Posted by Bushguts View Post
I'm not complaining. Just looking for accuracy.
Try exercising arithmetic you learned in grade school... 13 gallons to fill... That means you have 3 gallons left in the 16 gallon tank.

Last edited by watchdevil; 10/4/12 at 02:18 AM.
watchdevil is offline  
Old 10/3/12, 07:17 AM
  #5  
V6 Member
Thread Starter
 
Bushguts's Avatar
 
Join Date: September 9, 2012
Location: Charlotte nc
Posts: 94
Likes: 0
Received 0 Likes on 0 Posts
Originally Posted by watchdevil View Post
Try exercising arithmetic you learned in grade school... 15 miles left... 13 gallons to fill... That means you have 3 gallons left in the 16 gallon tank.
you must not be good at math. so let me educate you. if this car gets 15mpg then that would mean i have 1 gal of gas left. and it should take 15 gal upon fillup.

did you come in here to break ***** or help. if your not going to be any help then dont comment
Bushguts is offline  
Old 10/4/12, 01:46 AM
  #6  
Shelby GT350 Member
 
watchdevil's Avatar
 
Join Date: February 5, 2008
Location: Chattanooga
Posts: 2,339
Likes: 0
Received 3 Likes on 3 Posts
Originally Posted by Bushguts View Post
you must not be good at math. so let me educate you. if this car gets 15mpg then that would mean i have 1 gal of gas left. and it should take 15 gal upon fillup.

did you come in here to break ***** or help. if your not going to be any help then dont comment
You must be assuming that the 15 miles-to-empty readout is accurate along with the fuel gauge, which you have already proven that they are not by stating at 15 miles-to-empty it took 13 gallons to fill up your 16 gallon tank.

This also means your 15 MPG average figure in the info center may not accurate because the info center uses the data from fuel gauge sending unit and odometer to determine MPG and miles-to-empty.

The tank is 16 gallons and you said it took 13 gallons to fill it. That leaves you with 3 gallons left in the tank before you filled it. That is real math (16 gals - 13 gals = 3 gals). There is no other math in the world that can say you had less. Please explain how it can physically be any less?

Where are you getting your figure of 15 mpg from? Actual MPG is an average that can only be determined by dividing the number of miles traveled since the last fill-up by the number of gallons of gas used to fill-up the tank again. If you want accuracy, doing calculations this way is the only way you are going to get it.

Assuming your vehicle in fact gets 15 mpg then that means before you filled it up it had a remaining 45 miles range left for travel (15 mpg x 3 remaining gallons = 45 actual remaining miles to empty). If you filled up using 13 gallons of gas, that means you traveled 195 miles since your last fill-up (15 mpg x 13 gallons = 195 miles). Your entire tank travel range at 15 mpg is 240 miles (15 mpg x 16 gallons = 240 mile tank range).

As I said earlier, Ford designed a margin of error into the driver information system so idiot drivers don't run the tank completely dry and burning up the fuel pump. There is nothing that can be done to give you an truly accurate fuel gauge reading. It's not a defect nor is it something that can be "corrected" just to satisfy you. This is completely normal for every Mustang. I have owned two S197 Mustangs, a 2008 and my current 2010 and the fuel gauge, miles-to-empty and MPG info functions exactly the same.

I have had 18 different cars of various makes and models over the past 32 years and none of them have ever had an "accurate" fuel gauge.

Last edited by watchdevil; 10/4/12 at 02:14 AM.
watchdevil is offline  
Old 10/4/12, 10:57 AM
  #7  
Bullitt Member
 
AndreaCristiano's Avatar
 
Join Date: March 22, 2011
Location: NJ
Posts: 223
Likes: 0
Received 0 Likes on 0 Posts
Why is everyone being such douches? The guy is just asking a question!
AndreaCristiano is offline  
Old 10/4/12, 11:04 AM
  #8  
Mach 1 Member
 
Rog13GTCS's Avatar
 
Join Date: April 3, 2012
Location: Indy
Posts: 730
Received 50 Likes on 44 Posts
Originally Posted by Bushguts View Post
I have a little over 1k on my car. When it says I have 15 miles left I go and fill up and it takes 13 gallons. Why is it still off after this kind of mileage. And my gas needle is on E while this is happening. I can't judge how many miles I truly have left. This is a pain because I'm spending money too soon.

Does this happen to anyone else? If so what did you do to fix this? It's so annoying.
I get the 50 mile to fillup early, and I ignore. I havent done anything to fix or change it.

I check the Trip a/b - I found that it give me a close picture of where I'm at. I filled up the other day and it said I used 12 gallons and I put 12.3 in. Not 100% accurate, but gets me in the ballpark. Just remember to reset at fill up.

I did find this thread talking about the same thing. Hope that helps.
Rog13GTCS is offline  
Old 10/4/12, 11:27 AM
  #9  
Bullitt Member
 
AndreaCristiano's Avatar
 
Join Date: March 22, 2011
Location: NJ
Posts: 223
Likes: 0
Received 0 Likes on 0 Posts
Originally Posted by Rog13GTCS

I get the 50 mile to fillup early, and I ignore. I havent done anything to fix or change it.

I check the Trip a/b - I found that it give me a close picture of where I'm at. I filled up the other day and it said I used 12 gallons and I put 12.3 in. Not 100% accurate, but gets me in the ballpark. Just remember to reset at fill up.

I did find this thread talking about the same thing. Hope that helps.
I find this method is also much more accurate
AndreaCristiano is offline  
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
NC07GTCS
General Mustang Chat
43
9/10/17 04:47 PM
mx5jhb
2005-2009 Mustang
3
9/30/15 04:44 PM
captainEO
Warranty and Service Issue
1
9/24/15 08:42 PM
Mrmiles1369
2005-2009 Mustang
3
9/13/15 06:37 PM


Thread Tools
Search this Thread
Quick Reply: Gas gauge and digital gas gauge innaccurate


Featured Sponsors

Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service

© 2019 MH Sub I, LLC dba Internet Brands

We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon.com and affiliated sites.