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Discussion Starter #1
After I fill my tank up it smells like fuel until the level goes down. What can cause this?

Also my gas gauge always reads empty. Could this just be my float isn't floating anymore? Where can I buy a new one?

It's a 94 bronco 351.
 

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yo,
Check that gasket inside cap; mine was so brittle that I got a CEL and Code; Dealer has the best one with tether; Stant caps do not have that tether & cost almost same $

Next, check Fill & Vent Tube


Basically how the system works is the valve you see on top of the tank is the evaporative emission valve (9B593) mounted on the top of the fuel tank (9002); is used to control the flow of fuel vapor entering the fuel tank vapor delivery line which conducts vapor forward to the evaporative emissions canister (EVAP canister) (9D653) in normal circumstances.
If, due to extreme conditions, excessive pressure is generated inside the tank, the purge port opens up, allowing fuel vapor to escape to the atmosphere, and stabilizes pressure inside the fuel tank.
The evaporative emission valve has a head valve which prevents the fuel tank from overfilling during refueling operation. The evaporative emission valve also has a spring supported float assembly, which prevents liquid fuel from entering the vapor delivery line during severe handling, steep grades or in the event of vehicle rollover. Now when the engine is off the pressure from tank will open the valve and let vapors go into the vapor lines to the carbon canister in the front. Then when you start the vehicle the canister purge valve will open and draw the vapors from the canister back into the engine to be re burned. Now the canister is sealed and should not leak but it does not really hold pressure. The valve in the tank should close when the pressure equalizes in the tank. and the carbon in the canister absorbs the vapors and holds them until the engine is started. Also check the canister purge solenoid make sure it clicks good if you supply power on the red wire just to make sure it isn't stuck and you can unhook the hose and pull a vacuum on not and make sure it is not leaking

See my site @ http://www.broncolinks.com/index.php?index=214 for info on above items;
Such as;
Fill Pipe Depiction & Parts Break-Out Diagram
Source: by Steve83 (Steve, That dirty old truck)
http://www.supermotors.net/registry/media/283481


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gas gauge always reads empty

Testing & Connector Pin-Outs in 92-96 Bronco; Sender Range: 16 Ohms Empty; 160 Ohms Full; "... gauge that pegs past full indicates an open circuit (broken wire; unplugged connector; corroded terminal; burned sender) on the Y/W wire. gauge that pegs past empty indicates a short to ground (pinched to the frame, body, or dash supports) on the Y/W wire, OR a sunk float. gauge anywhere in between that doesn't move indicates an open circuit (blown fuse; corroded terminal) on the power (battery) side of the gauge OR a bad instrument cluster ground at C251 pin 9. The terminals of C251 (& C250) are known to corrode & lose contact. Polish both the connector pins AND the film circuit pads with brown paper or a pink eraser. The larger version of C441(WPT454) was used until 93. The level sender can usually be disassembled & repaired by bending the wiper arm inside the plastic housing to apply slightly more force..."
Source: by Steve83 (Steve, That dirty old truck) at Testing & Connector Pin-Outs in 92-96 Bronco; Sender Range: 16 Ohms Empty; 160 Ohms Full;
"... gauge that pegs past full indicates an open circuit (broken wire; unplugged connector; corroded terminal; burned sender) on the Y/W wire. gauge that pegs past empty indicates a short to ground (pinched to the frame, body, or dash supports) on the Y/W wire, OR a sunk float.
gauge anywhere in between that doesn't move indicates an open circuit (blown fuse; corroded terminal) on the power (battery) side of the gauge OR a bad instrument cluster ground at C251 pin 9. The terminals of C251 (& C250) are known to corrode & lose contact. Polish both the connector pins AND the film circuit pads with brown paper or a pink eraser. The larger version of C441(WPT454) was used until 93. The level sender can usually be disassembled & repaired by bending the wiper arm inside the plastic housing to apply slightly more force..."
Source: by Steve83 (Steve, That dirty old truck) at SuperMotors.net

For a New Sender;
http://www.fordparts.com/
Select Model
year, Bronco etc,

Air and Fuel Delivery

Fuel Pumps and Related Components 5.0L - 8Cyl, 4WD 9A299 Fuel Sender (Gas) $186.35

http://www.fordparts.com/Commerce/CatalogResults.aspx?y=1994&m=Ford&mo=Bronco#Search

For replacement w/t dropping tank, Consider Cut-out Panel Fabrication for Fuel Pump/Level Sender Replacement Section for Links
Source: by various owners in my Site @ http://www.broncolinks.com/index.php?index=616

Get a patch panel from a Bronco or F series @ a yard. or
Patch Panel, 48in. x 16in. for 80-96 Bronco & F Series; $35.00 Source: by Jeff's Bronco Graveyard http://broncograveyard.com/bronco/i-34094-rear-bed-patch-panel-48in-x-16in-.html
 

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Mine was doing this also and it was the gasket under the lock ring on top of the tank.
 

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sounds like the seal on the top of the tank ring not that bad if the tank is empty. put a sending unit in at same time.
 

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Discussion Starter #8
OK so I dropped the tank and the breather valve has two hoses attached to it. One hose runs to the front of the vehicle and the other hose was pinched off. Is this normal?
 

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OK so I dropped the tank and the breather valve has two hoses attached to it. One hose runs to the front of the vehicle and the other hose was pinched off. Is this normal?
Not postive about your year (I have an '89). On mine one of the hoses goes out the rear and has a clip holding it to the rearmost frame crossmember. It has a little mushroom shaped cap on it.
 

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Check the welded inlet pipe to the tank - mine had a hairline fracture and would leak mostly vapour but a bit of fuel as well. It's the spot where the rubber hose connects to the tank - have a really good look at it. If it's fatigued, time for a new tank. I'm assuming your tank is metal.
 

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OK so I dropped the tank and the breather valve has two hoses attached to it. One hose runs to the front of the vehicle and the other hose was pinched off. Is this normal?
yo,
As j. r. Nice mentioned....

V REST Vapor Valve (also described by F__D as the evaporative emission valve) pic

by bigmatt

the valve on top of the tank is the evaporative emission valve (see F..D depiction 9B593) ,mounted on the top of the fuel tank )is used to control the flow of fuel vapor entering the fuel tank vapor delivery line which conducts vapor forward to the evaporative emissions canister (EVAP canister) in normal circumstances.
If, due to extreme conditions, excessive pressure is generated inside the tank, the purge port opens up, allowing fuel vapor to escape to the atmosphere, and stabilizes pressure inside the fuel tank. The evaporative emission valve has a head valve which prevents the fuel tank from overfilling during refueling operation. The evaporative emission valve also has a spring supported float assembly, which prevents liquid fuel from entering the vapor delivery line during severe handling, steep grades or in the event of vehicle rollover



Do you have the CEL lit?
 

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I had the same problem with my gas gauge reading empty as well. I replaced the sensor and that did the trick. Have someone take a look at your sensors and your gaskets.
 

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Discussion Starter #13
The fuel float had a pin hole leak in it. So I ordered a float and two gaskets. Hopefully that fixes all my problems.
 
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