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Fuel Level / Indicator issues?

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Morning everyone!

So, I've read online that there some TSB's for 2011-2012 mustangs regarding their fuel sending units and issues with the fuel readings etc.

My issue doesn't follow exactly what those TSB's addressed but I have noticed something just yesterday that made me think...

I filled up the car, at the time the car said 13 miles until empty and the needle was down nearly all the way.
When I filled up the car, it took nearly 14 gallons, so it was legitimately getting low.
But since then, the car's fuel needle is up to full but the car keeps saying 140 miles until empty. I know even with city driving that I do I'm normally getting quite a bit more than this. In addition, this is the first time for me that I've noticed it tell me that low of a range after a full tank fill up.

Anyone else experiencing issues like this? And if so did you have the dealer look into it? I'm contemplating having mine look at it next week.

When I calculate how many gallons the car's capacity is, and do the calculations based on what the car is telling me my average MPG is, the 140 miles doesn't begin to make sense. I know this math isn't exact, but it should give a fairly decent idea.

Mine is a 2013 GB Boss
 
If I do purely city driving it will give me a range of that regardless of what the current MPG avg is. You can clear its history by disconnecting the battery and touching the pos and neg leads together. This is called a KAM clear (kam=keep alive memory). There is an idle relearn process to do after that but its rather simple.

Start car let idle till the fan kicks on or ten mins. (best do to when car is stone cold) then turn on ac on max for one min then turn it off. go drive car for 10-15 miles driving normal. and you are done.
 
I had to have the fuel tank vapor canister and fuel gauge sender unit replaced to fix my fuel gauge problem. Every time I'd go to fill it, it would only go to 3/4 full, although I'm not sure the vapor canister had anything to do with it.
 
I stopped looking at the fuel gage since I too started obssessing about the readings. All I know is that it consistantly tells me at 1/4 tank that I have 50 miles until empty.
 
Hambone said:
I stopped looking at the fuel gage since I too started obssessing about the readings. All I know is that it consistantly tells me at 1/4 tank that I have 50 miles until empty.

Yeah, mine is pretty consistent at the 1/4 tank mark also. It was just something I noticed, I wasn't exactly worried about it, but didn't want to let something go if there was a fix.
 
There are some strange algorithms for the DTE calc. It is taking into account recent MPG history, but I don't know exactly how much and how far back it uses the data. The annoying part is when you hit the 50 mile to empty warning, it's not figuring the 'reserve' amount in the tank. My Edge is the same way and it really bothers me when on a road trip to take a stop for gas way earlier than needed and top off the tank with only 12 gallons.
 

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