So my daughter's 4.0 has developed an 'issue'...

Hi all, first time poster here. I'm decent with cars, but have almost zero Ford experience. My daughter has an '05 4.0 that has been a great car. Last week, she called me saying that the car had died on her while driving and she was at a gas station. I went to check it out, and the car started right up, and I drove it back home several miles without incident. It had two codes, and I apologize that I don't have the exact codes in front of me. I was going to go out and re-read them but my daughter is out with friends and took her keys. :/ The codes translated by my cheapo reader said something like "Fuel Pressure High Bank 2". At any rate, I told her to try warming up the car before driving and to be careful, and i would delve into it that weekend.

Well, two days later her car stumbled and died in traffic. Since the motor wasn't running, the brake booster was not working and she rolled into a stopped minivan. :(

So now, while I am searching for a hood and headlight buckets and installing her new radiator, I still need to address the original problem. My wife's uncle is a drag racer and engine builder with a lot of Ford savvy, and he thinks it is the fuel pressure regulator.

Hopefully tomorrow I can re-scan the codes and add them to this post. Until then, I'm open to wild-arse theories. :) Thanks in advance.
 
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Hi all, first time poster here. I'm decent with cars, but have almost zero Ford experience. My daughter has an '05 4.0 that has been a great car. Last week, she called me saying that the car had died on her while driving and she was at a gas station. I went to check it out, and the car started right up, and I drove it back home several miles without incident. It had two codes, and I apologize that I don't have the exact codes in front of me. I was going to go out and re-read them but my daughter is out with friends and took her keys. :/ The codes translated by my cheapo reader said something like "Fuel Pressure High Bank 2". At any rate, I told her to try warming up the car before driving and to be careful, and i would delve into it that weekend.

Well, two days later her car stumbled and died in traffic. Since the motor wasn't running, the brake booster was not working and she rolled into a stopped minivan. :(

So now, while I am searching for a hood and headlight buckets and installing her new radiator, I still need to address the original problem. My wife's uncle is a drag racer and engine builder with a lot of Ford savvy, and he thinks it is the fuel pressure regulator.

Hopefully tomorrow I can re-scan the codes and add them to this post. Until then, I'm open to wild-arse theories. :) Thanks in advance.

On your car there is no fuel pressure regulator. Instead, there is a fuel pressure sensor that tells the computer what the rail pressure is and the computer modulates the fuel pump to maintain the desired rail pressure on the return less system. It's not uncommon for the fuel pressure sensor to go bad and cause loss of power or a stalling issue like you described. Obviously, the exact codes you are getting would help but that is my theory based on what you described :)

Here's a video that details where that sensor is at:

View: https://www.youtube.com/watch?v=IoLNytDx1N4
 
Yeah, that's the part I'm talking about. O'Reilly's database calls it a 'Manifold Absolute Pressure sensor' which makes no sense.

I guess it makes sense that this sensor could give a false high reading, which jives with the codes, and that could cause the computer to reduce the fuel pressure and starve the motor, especially when you aren't up to operating temperature yet and you need more fuel.

I've already bought a new sensor, so once I get the radiator replaced I'll try it out and see where we are. Meantime I'll rescan it tonite and post up the codes.
 
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OK, so here are the codes. I don't remember the Intake Air code from before but there it is...

P0113 - Intake Air Temperature Sensor 1 Circuit High
P0175 - Fuel System Rich - Bank 2
P0193 - Fuel Rail Pressure Sensor Circuit High Input

Any further advice welcomed. :) @Hoytster
 
Pic of daughter's ride just because people like pics. Don't hate on the badge engineering, the original owner added all the GT bits...
DSC_0328.JPG
 
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And since I have a before shot, here's a current pic. :( The hood is actually fully latched in this shot. You can see the new radiator in place - I haven't screwed it down yet so the condenser and trans cooler are still living la vida loca for the moment.

20191005_191709[1].jpg
 
OK, so here are the codes. I don't remember the Intake Air code from before but there it is...

P0113 - Intake Air Temperature Sensor 1 Circuit High
P0175 - Fuel System Rich - Bank 2
P0193 - Fuel Rail Pressure Sensor Circuit High Input

Any further advice welcomed. :) @Hoytster

Sorry, wasn't trying to ghost on ya. Been super busy lately.

So codes P0175 and P0193 together would still lead me to the look at the FRP sensor (though I would expect to see a P0172 code for bank 1 also). The P0113 makes it a little more complicated. The IAT is integrated into your MAF sensor and there could be multiple reasons for this code (bad IAT/MAF, bad ground, faulty connection/wiring).

Since you already bought the new FRP sensor, I would swap that out, check/clean the MAF connector, clear the codes, and take it for a drive and see if P0113 comes back.
 
Sorry, wasn't trying to ghost on ya. Been super busy lately.
No worries, I've had plenty to keep me busy. :) Besides this project, the fuel pump on my other daughter's Bravada bit the dust, and anyone that has changed a GM fuel pump knows that's a fun time. /sarcasm

So codes P0175 and P0193 together would still lead me to the look at the FRP sensor (though I would expect to see a P0172 code for bank 1 also). The P0113 makes it a little more complicated. The IAT is integrated into your MAF sensor and there could be multiple reasons for this code (bad IAT/MAF, bad ground, faulty connection/wiring).

Since you already bought the new FRP sensor, I would swap that out, check/clean the MAF connector, clear the codes, and take it for a drive and see if P0113 comes back.
OK, I thought about this anew just now and it dawned on me where the P0113 probably came from. I moved her car so that we could use a big tree and come-along to get the nose back into shape. When I did that I had already taken off the intake assembly, so the MAF was disconnected. I assume that code won't come back once I reassemble and clear the codes.

As for not seeing P0172, the car has intermittently thrown codes for the last 4-6 months, which would never come back when reset. By intermittently, I mean like 2 or 3 times in that span, so not often. I don't recall for certain but I am fairly sure the codes were always referencing bank 2. I've been assuming this current problem is just a worsening of that issue(s).
 
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Quick update. Finally got everything somewhat put back together and took it around the section. No stumble, no weird idle issues, no codes thrown, Got it up to operating temp and seemed to be running better than it had. So might be a bit early but I'm gonna tentatively call this a successful fix.

Only real issue is I forgot to put the clamp back on the lower radiator hose when I reassembled everything, so I spent a couple of hours tonight trying to get that back on. Finally gave up in frustration. My channellock pliers have gone missing and trying to do that clamp with a pair of Vise-Grips just doesn't work. :p So tomorrow I will get a new pair (whereupon the old ones will magically appear). Also plan to grab a worm-drive clamp just in case.
 
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