Anyone else had this happen?

It started about 4 weeks ago with a stall and failure to restart. A few codes popped up but the one that stuck out was P1233. Had to take it into a Ford dealer due to the location of breakdown. They confirmed the Fuel Pump Relay Module (FPRM) failed. It was a typical failure, corroded with water ingress. So ok, had them replace it. To note: They said the first FPRM failed out of the box so they special ordered me a new one. This might be an important detail. I picked it up and drove it for ~10 days before the symptoms came back. Those being loss of power and a slow chugging death spiral stall to failure. Then it blew a P0191 (Fuel Rail Sensor). So I replaced that myself. Ran fine for about a week (~3 50km trips to be fair) and then exact same thing.

Failure mode: Once up to temp, the truck would slowly stall out every ~10min. I could repeatedly get another 10 min of operation by simply disconnecting and reconnecting the harness to the new fuel rail sensor.

On closer inspection of the fuel sensor I also noticed a broken vacuum line which was part of the 4 port line connected to the fuel sensor. Replaced that. On family advice, I also replaced the fuel filter. Same failure mode afterwards. On internet research, I jumped the fuel pump voltage on the FPRM harness. Ran it at 80 psi for ~30min two times. Didn't run super well but it ran, no failure. Connected the FPRM back up and it failed again within 10min.

Took the truck today back into the shop (an independent local shop now). They are saying the FPRM is bad again. They said they confirmed it with a 'known good unit'.

My guy at the dump (ex mechanic) thinks it is the fuel pump (Despite the voltage jump check). My gut says it's a undiagnosed electrical issue. Thoughts?

P.S. The truck runs fine up until the start of failure. Rail pressure is a steady ~39 psi +/- 2 psi. You can watch the PSI drop out once it starts to fail. If you let it stall out it, the computer reliably throws another P0191.

 

FPDM - Fuel Pump Driver Module which is located under the truck above the spare tire. It appears you are using FPRM for the FPDM.
FRPS - Fuel Rail Pressure/Temperature Sensor which is located under the hood on the engine's fuel rail and has a vacuum hose connected to it.
FPM = Fuel Pump Module and is located inside the fuel tank, its the fuel pump and associated components in the tank
FPR = Fuel Pump Relay and its located in the Central Junction Box (CJB) basically the fuse box behind the passengers side kick panel

Your quote "Took the truck today back into the shop (an independent local shop now). They are saying the FPRM is bad again. They said they confirmed it with a 'known good unit'.
So if the shop says the FPDM (your FPDM) is bad then why not just replace it. After market FPDM are as low as $25 and I would guess ford Motorcraft is less than $100.

Issues like you are having can be frustrating but, in this case, the solution path appears straight forward. Make sure you clean the ground connection for the FPDM as it is located on the frame rail about 10" to the left of the FPDM. Also note that the connector and wiring harness to the FPDM can get corroded and cause a similar problem.

 

Thanks for the reply.

So yeah, I'm going ahead again with the replacement. We live in a rural area and I need by truck back. Not sure on your pricing (US based? I'm in Canada). Aftermarket modules are close to $200 here with tax. The Ford unit was $350. Labour and more so diagnostics for this one, probably $400. So I'll be into this now for ~$1500 as the Ford repair was ~$900. For a 15 minute bolt on/off part that I'm now paying for twice. The probability that two new Ford Fuel Pump Driver Modules themselves failed within two months in service (2MIS) is unlikely to say the least. If the third one fails(going aftermarket this time) then it has to be an electrical issue. And in that spirit, good point on checking the ground, I'll get the shop to do that .

I still don't understand how unplugging and re-plugging in the fuel pressure sensor gets me another ~10 minutes? Hopefully a third module replacement is the fix, we'll see....I'll report back in a few weeks (unless it fails sooner).

 

I am about 95% sure that the FPDM from the 2004-2008 crown victoria, lincoln towncars, mercury marques all used the same FPDM except that thiers are mounted in the truck and not exposed to road salts. Dead center of trunk right behind the rear seats. If I were you I would find a local scrap yard and purchased a used FPDM from them. Compare part numbers and I believe they are the same. U-Pull scrap yards are best since you control what you buy. I would skip further diagnostic expenses unless the FPDM replacement does not work.

My prices are Amazon and Ebay US based dollars.

Inspect the wiring and clean the ground and you should be good to go.

 

tradam75,

It’s been a few days since you last posted. Have you resolved this issue and if so, please post the solution? Feedback is important so that we all learn solution paths to these issues.

Thanks in advance

Jimboy

 

I am having the same issue with mine. I replaced the fuel pump/ fuel filter, and the fpdm. nothing. took it to the dealership and they said it was the fpdm. After they replace it for the 7th time it worked for a couple days then failed on me again.

 

To casemonkey1,

I am assuming you have a Ford F150 2004 thru 2008 model year with the FPDM located above the spare tire under the truck bed

My thoughts on these frequent FPDM failures

These modules do fail but it is mostly due to corrosion and takes years for the failure to occur. Frequent failures especially with replacement units are noted in this Forum almost daily. Why?

Here are my bets
20% of aftermarket are probably defective. 5 to 10% of Motorcraft maybe defective but I personally believe they are more reliable than that, What's going on?

It has recently come to my attention that some of the replacement units are being installed with the ground wire connected to the FPDM mounting studs. These studs are brand new and would appear to be a great grounding point but there is a flaw in this thinking. The new studs are being threaded into the existing threaded holes, they look great BUT the hole they are threaded into is corroded and the studs are not a tight fit (they can be wobbled by hand) and can loose continuity (loose ground) causing the FPDM to work intermittently. The original grounding point was about six inches away from the FPDM and consisted of a tapered, thread cutting, bolt that cut its own threads into the steel crossmember when it was originally installed.

The reason the shops are saying "Oh it was defective" is because the replacement unit is working when the previous unit was not. My bet is that if they just loosened and then retightened the studs for the existing unit it would magically work again, for a while.
This is a wild *** guess but if the mounting stud is being used for the ground there is an 70% chance of future failure (loss of ground) causing replacement

Bottom line - tell your shop to use the factory installed ground connection. Remove it, clean it up, and reinstall in original location using its factory bolt. IF the mounting studs are being used for the grounding point then have them move it back to its as-design location using the original bolt.

 

To casemonkey1,

It’s been a few days since you last posted. Have you resolved this issue and if so, please post the solution? Feedback is important so that we all learn solution paths to these issues.

Thanks in advance

Jimboy

 

I had a similar issue with my wife’s 2012 ford escape recently. Battery was fine and crank was fine. Intermittent issues where it wouldn’t turn over until the 3rd or 4th time. Ford diagnosed it as a bad FPDM and the pigtail it’s connected to, so I bought the parts myself because labor for the FPDM seemed ridiculously high for two bolts easily accessible. Over the phone I was told it was because it would have to be reprogrammed which was a lie for a 2012 escape. Replaced the FPDM and bought the harness but didn't replace it because it seemed fine. It didn’t crank over the first attempt after part was replaced but I noticed this time that the relay was making a buzzing electrical noise. I retested with a different relay and got the same result. That’s when I noticed the relay didn’t fit securely to the fuse box. I could hold it down to get a good start every time or slightly wiggle it while running to get the engine to stall. I think this bad connection at the relay was causing the FPDM to get bad voltage and the PCM wouldn’t allow it to send power to the fuel pump. Fixed by bending the connection clamps back for a tighter fit at the relay

 

Go to Rockauto.com (out of madison wisconsin).....& price the FPDM there.It will be shipped to you in 2 days & you just might like the price.....Further more google Rock Auto discount code on this site & get the 5% discount it provides also...
Better yet here is a code 318855849281059112 This code is good through to midnight November 21, 2025....That code goes in the box marked :How did you hear about us" after applying code pay for your items !!... Amazon also sell that module...likely made in china by Dorman??

.