Wow! I'm glad it just the cleaner! I've never heard of putting a "cleaner", except for seafoam, in a near empty tank..

It's good that the problem has cleared up!

 

I have a 2004 lariat with 140,000 and the p0451 came on. Has anyone come up with a solution to this? I have even gone to fordparts.com and put in my vin number and it comes up with the sensor that attaches directly to the tank and mine is in a vent line on top of the tank! I called a dealer and after about 10 minutes and my vin he did come up with one he says will fit for 305.00! I can't find one on amazon or any parts houses, they all say it is the one in the tank that fits and no other options. I have been under the truck and I can see it is the one in the line. I had the same problem with this truck finding rotors for the front on this truck. Anyone else having parts issues like this? Any help with the tank transducer or sensor will be greatly appreciated.

 

Exact same prob. sensor is inline with hoses over the tank. Can't find part anywhere. looks like lines are molded to the ends of sensor, no clamps. going to try and get p/n off old one.

 

Hi:
I ended up purchasing the unit from Ford. I signed into Ford Parts to get the local dealer. My wife is looking for the receipt for it for the price I paid. Not sure if you have used the Ford parts to check prices before, but if you put in your dealer you will (at least mine did) give you a good break. You have to tell the dealer you looked at Ford Parts on line to get the better price. The part comes with all the replacement hoses in a big box. about 12"x3"x about 6 or7 feet. I had to send the parts manager a email telling him the vin and that the part had a number(I took it off the drawing on Ford parts) and he sent me a quote for the part back. My wife just found the part number for the sensor and hoses that I purchased. The part number for my 2004 4dr 5.4l Larit was 5L3Z*9J279*BA. The part lists at $318.30 and they sold it to me for $229.18 plus tax, total in calif. was $246.94. Here is a picture of the box shipping lable from Ford. Hope this helps. I spent alot of time trying to find one but ended up at Ford. This is the one that is on top of the fuel tank and I did end up dropping the tank to fit all the lines.

 

Thx! I appreciate your (and the wife's) help. I checked out fordparts and put in my 2010 VIN. They show the sensor p/n 9C052 on their diagrams but it doesn't show up as one of the parts to add-to-cart. It looks it is separate from the hose assembly because the hose has a separate p/n. Or maybe that is just the smaller hose next to it.
So many DTC codes are related to the tank pressure sensor, so it seems to work, but I'm only getting P0451, which is sensor out of range. It seems like the sensor is GOOD and BAD at the same time. Kinda reminds me of one of my kids. Im guessing it is electrical, not a leak, as mentioned in an earlier post. Either wiring harness, but more likely the internal circuit of sensor intermittently shorting or opening. I need a scan tool that can give live data of the sensor readout.
The code seems to get set some time between the engine being shut off, cool down, and next startup, not when running.
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The sensor reads a voltage depending on the pressure in the tank. When you start the engine it runs a test of the evap system. I just went out and checked the voltage of my tank when started. I can not remember the voltage when it was bad, but I remember that there was a good difference when I changed it. The voltage when I start the truck was at 2.5** volts. The test started right away and the voltage started and the voltage started to drop. With in 1 minute it had already dropped to 2.3** and I opened the fuel cap and it went back to 2.5** volts. When mine was bad it started off by about .2 or .3 volts. The sensor is very sensitive to voltage change as the range total is less then 1 volt. It did change down from that so the sensor was working, but it would not go to the 2.5 neutral area and that was why the not in range fault would come up. I tested it with a meter under the truck and finally got the Torque program for my phone and tablet. The program is free or you can pay 5.00 for the upgraded version. I can't remember if it will give you the tank pressure voltage in the free version as I bought the 5.00 version right away. I bought the bluetooth torque obd2 adapter for something like 5 or 10 dollars on line. So for less then 15.00 I have something that helped me to test the sensor with live information and show me the difference after changing the part. So if the sensor does not start off at somewhere near the 2.5 range is will not read good. I hope this helps. Mine is a 2004 so I hope the readings are the same for yours. At least this might give you somewhere to start. Have a nice day.

 

Hah, too weird, I'm usingoing Torque app too, just free... it displays live O2s and Short term trim, but not tank or fuel line pressure. Time to part with a little $. Sounds like your sensor and gas cap were OK, but bad hose that came with it. But you got it fixed.

 

@rlounsbu I KNOW this is an OLD resurrected thread - but it's still relevant for those with this code.

EVERYTHING @amtpdb1 told you is spot on. As Torque Pro users - I might offer further assistance. I have discovered and worked out gauges for a BUNCH of OBDII Parameter IDs for the EVAP System on my 2004 5.4L Lariat, and a Torque Pro dashboard that monitors everything about the EVAP system. I've been planning to post it - with downloadable CSV file of the 'custom' PIDs and formulas- for benefit of other Torque Pro users. Here's a Screenshot:



------------ Brief Description of Gauges - and their purpose/meaning as to function of the OBDII EVAP Monitor routine.

Intake: Intake Air Temperature. Evap Monitor routine will NOT run below 40º or above 90º.
Speed: Vehicle Speed. Evap Monitor is disabled below 40 MPH.
EVAPSOAK: Evap Monitor is disabled if engine 'OFF' soak has not been 8 hours.
FLI: Fuel Level Indicator. Evap Monitor is enabled only between 15% and 75% fuel tank level.
EVAPMODE:
...-1 = Evap Monitor Not Running (disabled)
....0 = Phase 0, entry conditions not met
....1 = Phase 1, Initial Vacuum Draw down
....2 = Phase 2, Vacuum Stabilization
....3 = Phase 3, Vacuum Hold and Decay
....4 = Phase 4, Vacuum Release
....5 = Phase 5, Vapor Generation
....6 = EVAP test completed
EVMV: Evaporative Vapor Management Valve (N/C) (a/k/a Purge Valve) connects to Intake Manifold vacuum port. This valve is 'modulated' open and Fuel Tank Pressure Sensor monitored to check system integrety / leaks.
FTP_InH2O: Fuel Tank Pressure converted into Inches of Water
EVAPCV: Evaporative system Vapor Management valve (N/0) vents through known resistance of Carbon Canister flow.
CCL_ON: Check Cap Lamp illuminated on instrument cluster.
FTP Pa: Fuel Tank Pressure in Pascals (the international standard OBDII measurement).
FTP_V: Fuel Tank Pressure in Volts.
EVAPCP: Evap canister Purge commanded
EVAPCVF: Evap Canister Vent Valve FAULT flag
EVAPCVFM: Evap Canister Vent Valve FAILURE MANAGEMENT MODE
EVAPO20D: Evap '.020' Leak Test conditions not met. (Trucks exempt from the .020" leak test)
EVAP020C: Evap '.020' Leak Test Completed. (Trucks exempt from the .020" leak test)
EVAP020R: Evap '.020' Leak Test Ready (Trucks exempt from the .020" leak test)
EVAPSTAT: Evap Monitor Test COMPLETED this Drive Cycle.


The attached "CSV" file contains the "NON-STANDARD" PIDs that are not included with Torque Pro. (Vehicle Speed and Intake Air Temperature) are the only ones that are included with Torque Pro. So the remainder must be added. The attached CSV file (named 'Monitor EVAP System v1-1.CSV') can be downloaded and copied to your android device in the file folder named .Torque\ExtendedPIDs . Leave it in flat 'text' file format (ie: don't let EXCEL do fancy stuff to it). Just copy it as a text file with '.csv' extension into the Torque extended PIDs folder on your phone.

Then when you go to >Settings >Manage extra PIDs/Sensors - Menu >Add Predefined Set, you can select the file by its name. Then when you go to a new dashboard page you can ADD the gauges as depicted above - or whatever type gauges you prefer.

If you have trouble PM me or post back for assistance. This whole scheme works great with Torque for expanding its capability endlessly.

 

Awesome! FTPS is what Im looking for. The others will help too. Best post ever.
I setup screens to show when the Evap cycles complete, O2 sensors and Trims, and some basic gauges, but some are dead. Multi-pages are nice because it all can't fit on one page. Does the Pro version support two-way to allow programming?

the half hidden display shows open or closed loop.


Screen shot taken while OBD not conneted so no data but most work when engine is running.

 

There is 'actually' a lot more valuable information in your Monitor screen shown in the first screenshot above that many realize. Understanding that the PCM runs continuous 'OBDII Monitor routines' each drive cycle. (There's about 9 of them applicable to most vehicles). After ALL monitor routines successfully complete, the PCM increments its "TRIP COUNT".

Paying attention to which one or ones are having trouble (or a long time) to complete suggests something in THAT system is probably running near or occasionally outside factory spect ----- a DTC is imminent.

If you get Torque Pro, you might find this dashboard helpful. I located the OBDII flags for each of the monitor completion routines on my truck and created a Torque Pro dashboard to monitor their status and show trip flag when they are completed. LIKE THIS:



I posted the Torque screen and CSV file here:https://www.f150forum.com/f4/how-use...7/#post5992223

 

. It passed emissions test at last. I still don't believe the fix... just a squirt of electronic cleaner on the Mass Air Flow sensor. Or maybe it was wiggling the connector on the fuel tank pressure sensor when I was trying to find it. Someone mentioned that it could start corroding if expose to salty water. It saved me the cost of the sensor (for now) from Ford, but it still $UX that you can only get it from Ford. BTW, the connector alone is readily available... no more wondering why that is.
Also, the extra PID trick for the free version of Torque doesn't seem to work. It uses .DAT txt file versus .CSV and the entries for each PID is a different format. Still may be possible, just need someone that wants to try and hack it.

 

Thanks a $Million for the update! It's my gratification.
Thanks for the extra info: "DAT" for Torque 'Lite'. I've spent all my time 'hacking' for PRO version. But it is all for the satisfaction of beating he system.
I suspect your giggling the connector on the FTPS trying to find that little dude is what saved the day.

Happy torqueing from South Texas.

 

I had an EVAP problem in February of '17. Squirrels had got on top of the gas tank during a snowstorm and chewed every hose up there. A quick key to the problem is if you smell gas around behind the cab or even in the cab, you probably have damaged or cracked hoses in the tank area. This is not something to screw around with.
Now several times during the winter I will spray some '3-in-1' Garage Door Lubricant (mostly very smelly silicone) all over the top of the tank. This is actually good for the rubber parts and apparently the rodents hate it - also makes it slippery as hell up there. This is also a great preventive treatment for the Fuel Pump Driver Module.

 

I recently took the bed off of the truck ( 2010 F-150 XLT) and was able to get a good look at the sensor and hose assembly on top of the tank. Besides the sensor being molded right into the hoses there are 3 other hoses also molded into the assembly. I found a new sensor online by searching for the part number off of the top of the sensor ( 9U5A-9C052). With open-access I tried removing the old sensor from the hoses. Absolutely no luck. I even put the heat gun to it three different times but it would just not come off. These are not rubber hoses they are heat shrink nylon . The sensor is not meant to be replaced alone. Since it is critical that it has no leaks at all Ford wants you to buy the entire assembly. There is also a replacement kit that you can use to cut the sensor out and replace it. There is a video online showing how it's done with a Dorman kit on a Mustang. I have not tried it yet because the sensor seems to test okay... 2.5 volts when at atmospheric pressure. Reference checks at 5V and ground connection is solid. I suspect partial blockage in the lines or canister which makes the sensor not go immediately up to 2.5 volts after it's been sucked down and then vented again. All g with the bleed up I also still need to check that the system holds vacuum which can be done simply with vacuum pump and gauge. Torque is a good inexpensive DIY tool but it is about time to graduate. Besides, I need to program keys too. I'm gunna give Forscan a try.