I did it because it went bad. Was close to home when car started acting up and already had the sensor because I was going to replace it for the later revision part based on various forum threads.

 

I changed mine out to remove a possible weak link.

 

Can you describe the complaints more specifically?

 

I have not changed mine, as it is working fine. I have the digital dash and keep the A/F gauge up and regularly check it. I believe the issue mostly shows on WOT, so I do the occasional run on the highway to check that the A/F stays where it is supposed to. I also think that this is over reported and that the failure rate is not as bad as one would believe from the forums.

 

Mine have now driven 23.000 miles and nothing strange accurrance, but after read various ecoboost forums and the bad stories they told there Im a little bit worried!

 

I changed mine because I like tinkering with my car. I got the part on ebay for $20 and installed it myself, and now I have one less thing to worry about going bad.

 

Mine is a 2015 and I changed it because I was doing plugs and some other maintenance anyway and it was only like $30

 

Mine just arrived from CJPP. Changing it tomorrow.

 

CHANGE IT BE SAFE NOT SORRY ….VP

 

I changed mine after reading a post that was linked here. I don't know if failures are widespread or if it was a case of CYOA on the part of a tuner, but for $20-$30, I thought it was cheap insurance...one less thing to worry about.

 

I hope you guys that are replacing the sensor for good measure realize that a new unproven part is statistically more likely to fail than a part that has been performing correctly for a period of time.

That is the nature of all manufactured items. An items failure rate is highest when new and as it is used the failure drops to a low constant failure rate until some time in the future the part starts to wear out and the failure go back up.

In the case of the fuel pressure sensor Ford has been using the same part with the same part number in all gasoline engines since 2010 and still are. The after market part everyone is swapping in has some inconsequential minor visual differences but there is no evidence that it is any more reliable than the factory part (and it could have a higher failure rate).

Dave

 

I hope you guys that are replacing the sensor for good measure realize that a new unproven part is statistically more likely to fail than a part that has been performing correctly for a period of time.

.

The replacement sensor is neither new nor unproven, it has been in production and installed on new Ford vehicles since at least 2018 and so far hasn’t presented any indication of being problematic

In the case of the fuel pressure sensor Ford has been using the same part with the same part number in all gasoline engines since 2010 and still are. The after market part everyone is swapping in has some inconsequential minor visual differences but there is no evidence that it is any more reliable than the factory part (and it could have a higher failure rate).

Dave

Completely inaccurate, refer to Turbotigger’s post above.

The issue is presuming that the aftermarket sensor is "updated". If it was "updated" the factory would be putting it in new vehicles which they are not.

Also untrue, as Turbotigger posted above, the upgraded sensor has been installed in new vehicles since at least mid-2018.

With all due respect, you have many educational and informative posts, which I’m greatful for, as I’m sure many others are as well. Posting unfounded claims like this as fact detracts from the many great contributions you make.

I have been an engineer supporting manufacturing for over 40 years and every time you go to a different supplier for a part made to the exact same spec it is almost inevitable there will be visual differences. Considering the millions of this sensor Ford has put in all their gasoline engines for the past 10 years the only conclusion i can make is it is nothing more than a part from another supplier.

40 years as an engineer and that’s the “only” conclusion you can make, lol? Would a possible conclusion not be that maybe Ford recognized a weakness in the existing sensor and in response, designed a sensor less prone to failure?
Is it fair to assume you were a project engineer and not a process or production engineer?

I call it aftermarket because it is not the same as the one that comes from the factory.

Dave

I call it OEM because it is the exact same as the one that comes from the factory since 2018.

AFAIK, BU5Z-9F972-CA is the only one currently in production, as the old style (BU5Z-9F972-B) was phased out.

Also, Motorcraft offers genuine FoMoCo replacement parts, is owned, endorsed, and trademarked by Ford, built to Ford specifications, and can be picked up at any Ford dealership as a direct replacement. In many cases, their parts are built on the same assembly line alongside FoMoCo replacement parts, a far cry from what most consider as aftermarket.

 

I also read on the internet that not only change the LPFS but also the Evap Purge Solenoid (FR3Z-9G297-H).

 

I’m with Dave on this one.
Of all the eco boosts we’ve gotten here at the shop only one needed the evap valve swapped out and none have had low pressure fuel sensor issues.
If you want to swap them out for peace of mind, have at it.

 

Okay, then I can go quiet sleep tonight!

 

I have popped codes for both of them. The fuel sensor got swapped by Ford on their dime, I did the evap valve myself.

 

That's the key; you got a code indicating there was an issue. Swapping either sensor with no symptoms or codes is not a good use of your resources in my book.

Dave

 

I agree, but some people just want that peace of mind.

 

@dgc333 The fuel pressure sensor has indeed been shown to be an issue when data logging, FRP actual vs FRP desired is able to show if the sensor is functioning correctly. Many who have thrown the code and data logged these 2 parameters show inconsistencies between the 2 with the stock sensor, I've yet to see or hear from my tuner where the new sensor didn't fix the issue.

Not disagreeing with you that the stock sensor is probably fine on most cars, but it's such a cheap part that can have such a big impact on your motor, why not change it out for peace of mind?

I've yet to see any data logs from anyone with the updated sensor that shows FRP actual being less than FRP desired.

 

The issue is presuming that the aftermarket sensor is "updated". If it was "updated" the factory would be putting it in new vehicles which they are not.

There are some nonconsequential visual differences but no one has presented any evidence that there is anything about it that is functionally different or that it is more reliable.

I have been an engineer supporting manufacturing for over 40 years and every time you go to a different supplier for a part made to the exact same spec it is almost inevitable there will be visual differences. Considering the millions of this sensor Ford has put in all their gasoline engines for the past 10 years the only conclusion i can make is it is nothing more than a part from another supplier.

Dave

 

The issue is presuming that the aftermarket sensor is "updated". If it was "updated" the factory would be putting it in new vehicles which they are not.

There are some nonconsequential visual differences but no one has presented any evidence that there is anything about it that is functionally different or that it is more reliable.

I have been an engineer supporting manufacturing for over 40 years and every time you go to a different supplier for a part made to the exact same spec it is almost inevitable there will be visual differences. Considering the millions of this sensor Ford has put in all their gasoline engines for the past 10 years the only conclusion i can make is it is nothing more than a part from another supplier.

Dave

Actually mid 2018 Ford started putting the "new" sensor in the eco mustang, i can't speak for other 2.3 vehicles, but the mustang was definitely updated in 2018.

It's also not just a visual change.



The item ordered was BU5Z-9F972-B. However, the actual part number on the sensor is BU5A-9F972-CA. (New sensor on bottom). According to some posts, the 2018 Mustangs still have the old sensor.

It appears the part has been revised by Ford. The revised sensor has an additional hole for atmospheric pressure.

 

Not sure why you’re referring to the sensor as aftermarket. It is an OEM replacement that can be purchased directly from Ford.

 

eBay a reliable source for these? Everywhere else is about twice the cost, wondering if there’s good reason for it

 

Possibly, I bought mine directly from my local ford dealership for $23 plus tax.

 

Question for you Dave, you seem to know what you're talking about, so I trust your answers.
Would that tiny hole shown on what people say is the "NEW" part have any effect on the wafers deflection or response time as compared to the 'sealed' part, or would that portion of the electronics be separated from atmospheric venting? Does that hole represent a possible design update or might it just be a location jig for assembly orientation?

 

Until some one opens one up we will not truely know. As you say it could be a tooling hole or a hole to inject potting compound to environmentally seal/protect the sensor chip & wiring or be an atmospheric reference hole. Back in the 80s we were one of the first companies to introduce a pressure transmitter for process control applications (think refineries and power plants) and to keep the chip isolated from the process there was a tin stainless steel diaphragm inbetween the process and the chip. This required the space be filled with fluid to transfer the fluid, it could be a fill port for that.

The problem with it being an atmospheric port it is in the worst possible place. Over time it will get plugged with crud. If it was necessary i would vent through the connector.

Keep in mind that from extreme low barometric pressure and extreme high represents about 3.5 psi and from sea level to 6000ft altitude represents about 10 psi. These extremes likely are not important to keeping adequate fuel at the high pressure pump.

Dave

 

Until some one opens one up we will not truely know.

I don't think that's necessary. It doesn't always have to be an episode of 'sliced'...although I did enjoy that show thoroughly. ?I did some digging into how "Pressure Transducers"operate. Here is what I found:

https://www.teesing.com/files/downl...wnloads/whitepapers/setra-field-guide-to-understanding-pressure-transducers.pdf

I knew there was something different just from the eyeball test, so I started reading into the different types of sensor and how they work. Basically, the old sensor is a "sealed" sensor. It does not use an atmospheric reference point, as the new gauge does...indicated by the hole on the side.

The "old" gauge seems to be what is called an "absolute pressure" gauge, meaning that it is measuring lowside fuel pressure, referenced ONLY to its sealed, vacuum housing. The new gauge is either a "differential pressure gauge", or, more likely, a "gauge pressure" gauge. (Their terms, not mine...and you can read more about each in the link). The problem with "absolute pressure" types of gauges is, and I quote:

"The major drawback is the trapped volume of air is sealed in and becomes is sensitive to temperature changes; both ambient and pressure media. When sealing a volume of air in a chamber the “Ideal Gas Law” presents challenges that are unavoidable. When talking about the ideal gas law as it pertains to a sealed gauge pressure transducer, the trapped volume of air expands or contracts with temperature changes and has a direct effect on the force applied on the backside of the diaphragm. The initial force on the back side of the diaphragm increases or decreases based on the direction of the temperature change. The lower the pressure range the greater the impact it has on the sensors overall accuracy "


So the "reference port" is ABSOLUTELY INDICATIVE that the old lowside fuel pressure sensor is not working in the same manner as the new one.

 

Dave, Boeing needs you!

 

LOL, actually i had an offer from Boeing Space Systems right before i accepted my current position at Lockheed Martin. Wasn't interested in relocating to California.

Dave

 

@gatornek nice find!

 

Thanks. It just seemed to me that the hole was "purposeful" in its design....so I went on a mad search to see how these things actually work.

 

Great info here. Hey yes.. FYI... the old model was on my 2019 PP Eco.

 

Great info here. Hey yes.. FYI... the old model was on my 2019 PP Eco.

View attachment 35821

Interesting, there have been mixed reports of some models after mid 18 still having the old sensor, and others saying they were all replaced.