Ive got a 06 F350 PSD and when I fill the tank the guage reads empty for about 50 miles then it comes back up to full. Took it to the dealer and they said I would have to bring it on a empty tank so they could fill it up and see the problem. Anyone else had this problem?

 

Do you leave the key on when you fill up? I believe this is normal. Mine does the same only when I leave the key on.

 

Don is correct . Key on or left running while fueling will screw up the reading for awhile.

 

You could listen to these guys or take it to the dealer on empty so they can fill your tank for free (warranty)

 

That is funny........and he is right......

 

Or they will give it to the lot guy(gal) and he will fill it with gasoline.

 

Fuel Gauge

The instrument cluster receives the fuel level signal from the fuel level sensor, part of the fuel tank unit. The fuel level sensor measures variable resistance in the fuel tank depending on the current fuel level. When the fuel level is low, the resistance in the unit is low (15 ohms ± 2 ohms). When the fuel level is high, the resistance in the unit is high (160 ohms ± 4 ohms).

The instrument cluster uses 4 different operating modes to calculate the fuel level:

anti-slosh (default mode)
key OFF fueling
key ON fueling
recovery
After a fuel fill up, the time for the fuel gauge to move from empty (E) to full (F) ranges from 2 seconds to 55 minutes depending on which operating mode the fuel gauge is in.

The default fuel gauge mode is called the anti-slosh mode. To prevent fuel gauge changes from fuel slosh (gauge instability due to changes in fuel sender readings caused by fuel moving around in the tank), the fuel gauge takes approximately 55 minutes to go from full (F) to empty (E).

The key OFF fueling mode (2 seconds to read empty [E] to full [F]) requires 3 conditions be met:

The key must be in the OFF position when refueling the vehicle.
At least 15 percent of the vehicle's fuel capacity must be added to the fuel tank.
The instrument cluster must receive a valid key ON fuel sender reading within 1 second of the key being put into the RUN position. The key ON sample readings are considered valid if the fuel sender reading is between 15 ohms ± 2 ohms and 160 ohms ± 4 ohms. If these conditions are not met, the fuel gauge stays in the anti-slosh mode, which results in a slow to read full (F) event.
The key ON fueling mode (approximately 90 seconds to read empty [E] to full [F]) requires 3 conditions be met:

The transmission is in park (P) (automatic transmissions), or the parking brake applied (manual transmissions).
The key is in the RUN position.
At least 15 percent of the vehicle's fuel capacity must be added to the fuel tank.
In key ON fueling mode, a 30 second timer activates after the transmission is put into the park (P) position (automatic transmissions) or when the parking brake is applied (manual transmissions). When the 30 second time has elapsed and at least 15 percent of the vehicle's fuel capacity has been added, the fuel gauge response time is 90 seconds to read from empty (E) to full (F). When the transmission is shifted out of park (P) or the parking brake is released, the fuel gauge strategy reverts to the anti-slosh mode. This mode prevents slow to read full events from happening if the customer refuels the vehicle with the key in the RUN position.

Recovery mode is incorporated into the instrument cluster strategy to recover from a missing fuel level message during a refueling event. Missing fuel level messages result from intermittent opens in the fuel sender or its circuits. Recovery mode (empty [E] to full [F] approximately 20 minutes) is initiated when the following 2 conditions are met:

The instrument cluster is in the anti-slosh (default) mode.
The actual fuel level in the tank is greater than what is being displayed by the fuel gauge.

 

That should be put on a sticky. Answers alot of questions . I never knew why it did it just that it did. Thanks Haya

 

That is a lot to digest! I always fueled my Dodge running in order to baby the turbo as much as possible. It's not good to pull off the freeway while pulling 10,000+lbs in 100 degree+ heat and immediately shut her down just for fuel.

The 1 time I fueled the SD with the truck running I obviously got the VERY slow to react fuel gague, figured it wasn't good for it and stopped fueling with engine on. That really annoyed me but it sounds like it should have no adverse effect other than just taking some time to return to an accurate reading.

 

I agree. Nice to see you posting again Hayapower, great info on fueling up the Super Duty.

 

It has been added to the 6.0 Tech Folder - Thanks Hayapower!

 

I've never had any inaccurate appearing fuel guage readings in my '04 and I have fueled up running, off, on slow pumps and the quick fill pumps... That's some interesting tech info! Thanks....

 

Have had check engine lite come on 3 or 4 times when I topped off tank, trying to really filler up. Sometimes the check engine light goes out like on the next tank full or I've taken to the dealer(under warranty)and they reset it? The fuel gauge always acts normal. any comments?

 

Just in recent months I've filled up my 04 from near the 1/4 mark with the key off and when restarting the gauge goes to max empty and the warning light and chime come on. After a few momments the gauge goes back to where it was prior to refueling (1/4). It has taken some period of time (minutes to an hour) or number of engine restarts to finally get to the full mark. This has occurred 3-4 times. I haven't yet been to the dealer and probably wont after reading this thread.

 

Could be this:

Check Engine Light on with P0460 Fuel Level Sensor Code:
This may be caused by a miscommunication of fuel level ststus between the instrument cluster and engine computer. This code is set when the engine computer does not see the fuel level dropping it expects. It may be caused by customer-installed items, such as a remote start system that does not power the dash when activated, an over-sized fuel tank or in-bed fuel tank. If these conditions do not exsist, the engine computer should be reprogrammed using WDS/IDS version 43.4 or higher. This condition can also be caused by fueling with the engine running, parking on an angle, or driving up a long grade. In some cases the fuel level sender may be faulty, or have a sulfur build up on the sender and have code P463(use Chevron Techron Plus Concentrate to correct). TSB 06-13-11