GT500 pumps install issue - fuel level

[JimIII@JDM]

when brenspeed did my install, they said that when the tank gets below 1/2 tank. it can drop to 0,

they said to switch the wires

this happened on the way home from their shop, i switched the wires, now it does it when it's just below a 1/4 tank

??????

it'll start out at like 5 to e then down to 0 and then keep going

Your problem might also be because they possibly sold you an 05-09 kit and not the 2010 specific kit. If you get a 2010 GT500 fuel pump assembly it will solve your delema, which by the way we have in stock ; ) Call me at 732-780-0770

 

[beefcake]

Your problem is because they sold you an 05-09 kit and not the 2010 specific kit. If you get a 2010 GT500 fuel pump assembly it will solve your delema, which by the way we have in stock ; ) Call me at 732-780-0770

Hmmm, they told me the kit was a 2010 kit...

what is the diff why it reads below a 1/4 still after switching the wires?

 

[JimIII@JDM]

Hmmm, they told me the kit was a 2010 kit...

what is the diff why it reads below a 1/4 still after switching the wires?

I cant really explain why it reads at a 1/4 still only thing other than we had this problem last year on a 2010 car and only to find out there is a different intank assembly. Physically look the same right down to the wiring but I guess its getting a different signal for the fuel level indicator.

below I have a picture of the top hats from a 2010 and 05-09 setup with the part #s. Pull your back seat up and see which one you have...

2005-2009

2010 Mustang

 

[beefcake]

I cant really explain why it reads at a 1/4 still only thing other than we had this problem last year on a 2010 car and only to find out there is a different intank assembly. Physically look the same right down to the wiring but I guess its getting a different signal for the fuel level indicator.

below I have a picture of the top hats from a 2010 and 05-09 setup with the part #s. Pull your back seat up and see which one you have...

2005-2009

2010 Mustang

i'll check when i get home, thanks

 

[UNICORN]

I cant really explain why it reads at a 1/4 still only thing other than we had this problem last year on a 2010 car and only to find out there is a different intank assembly. Physically look the same right down to the wiring but I guess its getting a different signal for the fuel level indicator.

below I have a picture of the top hats from a 2010 and 05-09 setup with the part #s. Pull your back seat up and see which one you have...

2005-2009

2010 Mustang

great I was confused
thanks

 

[beefcake]

I cant really explain why it reads at a 1/4 still only thing other than we had this problem last year on a 2010 car and only to find out there is a different intank assembly. Physically look the same right down to the wiring but I guess its getting a different signal for the fuel level indicator.

below I have a picture of the top hats from a 2010 and 05-09 setup with the part #s. Pull your back seat up and see which one you have...

2005-2009

2010 Mustang

double checked. Mine is indeed an ar33, with the 11/11 date.

so it is a 10 kit, so now what???

 

[loots06]

Great, I'll try switching the wires first.

 

[Diabolical!]

I installed my GT500 pumps back in January of '08 using the Whipple supplied instructions. When I was finished the complete supercharger install, my fuel guage was reading zero. After driving myself nuts checking the wiring harness for two hours, I started switching the sending wires at random (probably not the brightest idea). It worked. Either the instructions were wrong or the wiring in the harness was wrong, but I suspect it was the wiring because of all the other people I know who followed the instructions from Whipple, I'm the only one who had the problem.

 

[RLF9409]

You got it!!!!!!!!!!!!
I dont have those aftermarket lines in it, but I did put a zip tie on the unit so it wont come undone when putting it back in the tank. I heard too many people not having the fuel gauge working when past 1/4 tank and most likely thats the problem. I should of put different fuel line on when I had the pumps out. Those plastic lines arent good at all.

Okay, so just installed the GT500 pumps, figured out the wiring issue, now have the fuel level issues...
I ensured that the float is working correctly. I had to ship my car back to the states yesterday and it could only have 1/4 tank. I noticed that whenever I am going up hill or give it some gas the fuel level goes to 0.
I am wondering if I pinched the intank hose? That's the only thing I can think of, that the pump is not drawing fuel from the passenger side sump? I also read that sometime this issues resolves itself after a full tank of gas?
Just wondering if anyone has suggestions? It will be sometime until I get the car back, Jul 5th or so, so I just want to be ready for when I pick it up. I have to drive it from CA to AZ, I guess I'll just be safe and keep it at half tank until I get it home...
I was thinking of just replacing the intank hose, when I have a chance. Would any fuel hose be ok? I am worried that a rubber hose would start to deteriorate from the fuel???

 

[908ssp]

I just installed the GT500 pump assembly from 2007 into my 2010 GT. The sending units read opposite. The resistance when the tank is empty is 16 ohms on the GT500 pump and 160 ohms on the 2010 GT pump and the opposite when full. The only way to fix that is to put the 2010 sender on the GT500 pump. I made a custom bracket which is not an easy solution.

 

[Jinx]

....

 

[stanglifemike]

I had the same problem with mine when I installed it. I swapped wires and pulled the pump/re-installed over and over again. Finally my Ford dealer gave me a number to a guy at Ford Racing. I explained everything to him and he sent me a new sending unit (float). Installed that and the problem was gone and hasn't came back for 7 months now.

 

[HankyGT]

I know I'm bringing this one back from the dead...

BUT, after screwing with mine for 3 days I found that Ford actually broke the electrical spade connection off the float when they ziptied the wiring together on the pump.

No Ohm/resistance output = gauge no worky.

Check to make sure you're getting a change in resistance through the full sweep of the float. You will need to use a digital meter as the analog won't measure such a finite sweep.

Hope that helps to some of you who've yanked pumps and switched sending wires in amazement when I should have checked the resistance first. Yes, the sending unit wires were backwards to boot.

Ford Racing FTL lol

 

[JeremyH]

Here is run down for the senders I posted in another thread.

The board inside the level sender changed the way it reads resistance in 2010.


05-09 GT and 07-09 GT500 reads 15 to 160 ohms low to high. The GT and GT500 level sender designs are physicaly different but read the same.


2010+ GT and GT500 senders read 180 to 30 ohms low to high, and again same physical design difference form the GT to the GT500.


So to use a 2010+ GT500 fuel hat in an 05-09 GT and have the fuel level read correctly you would need to replace the 2010+ GT500 level sender with an 07-09 GT500 level sender.


You can get one from ford.


There is another way of phyicaly taking the sender apart and trying to remove the ceramic circuit board form your sender and swapping it to the new one. But they are very easy to break and I wouldnt even mess with that.

 

[HankyGT]

Good post and dead on ^