Codes:

P0183: Fuel Temperature Sensor A Circuit High
P0191: Fuel Rail Pressure Sensor A Circuit Range/Performance
P0193: Fuel Rail Pressure Sensor A Circuit High

I have replaced the fuel rail pressure sensor and the sealed fuel pump driver module, but still have not had any luck getting the truck to run.

I think it may be the fuel pump but I’d love to exhaust other ideas before trying to remove a full tank of gas and troubleshoot down there.

A friend of mine suggested testing the fuel pressure but I’m not sure how to do that? I tried some other forums with no avail so any insight would be great! I’m a college student on spring break and have a week to fix this before classes start back up... Thank you.

2007 F-150, 5.4 V8 Triton, XLT

 

Fuel pressure can only be read with a scanner that can read the fuel pressure PID. You can do a quick and dirty check by disconnecting the fuel filter, get help to turn the key on MOMENTARILY while looking for gas spraying out.

Go to a parts store and rent/borrow an inline spark tester and a set of noid lights. The noid lights will see if the injectors are pulsing.

You won't be going back to class anytime soon. You will probably be finishing up the semester online.

 

glc,

Thank you, I will pick up a testing kit and hopefully that will lead to something!

I tried the truck with a scanner (Foxwell NT 301) and was able to look at the Fuel Rail Pressure (FRP) with the key on. Live data today had the PSI at 0.00 (key on ignition off, and same with key on ignition on) but the Freeze Frame data had it at 78.7 PSI. Does that mean the fuel pump has since then failed? The RPM's didn't even break 200 either.

Yes, all our classes will be online for the remainder of the semester. However, I'd love to knock out this problem before juggling classes again and my full time job which will now be part-time too...

Thank you!

 

Confirm you have no fuel pressure by disconnecting something to see if it tries to prime. If no fuel pressure, the pump has failed, the FPDM you installed is faulty, or something else is preventing the pump from running. Check voltages at the inertia switch and other points in the circuit. Check fuses and relays.

 

Before disconnecting anything, simply LISTEN carefully to see if you can hear the pump run when the key is turned from OFF to RUN.

Your fault codes indicate you have electrical circuit faults related to the FRP sensor. If there are circuit faults, the data you are reading is invalid and will likely lead you off into the weeds.

 

glc and projectSHO89,

I hooked up a manual pressure gauge to the fuel rail (no Schrader valve, so I just removed the pressure sensor and tapped in there) and the fuel pressure came back good at 46 PSI. There are no blown fuses and I've reset the switch tucked behind the fuse box. However, the condition is now worse. The truck will not try to turn over at all. It cranks for half a second, shuts the engine off, then the dials all flicker and go down and then everything turns off. All the OBDII data has also been erased, but on the bright side the codes have gone away.

I kind of understood mechanic stuff with the fuel line but this next development scares me. I will take the battery in to get recharged (free at autozone since I bought it there) and see if that changes things. What might be the cause of the engine not working at all now?

 

When you get the battery back, test for spark and injector pulses. When you reinstall the battery, clean all connections.

 

The battery helped and got the truck back to the original problem. I friend and I cleaned the crank shaft sensor and checked out some of the coil packs and spark plugs. We just used an in-line spark tester for this testing. It said they coil packs were communicating properly.

Additionally, the code P0351 Ignition Coil A primary/Secondary Circuit came up. We rotated the coil packs (swapped 1 and 2, and then 1 and 4) but the same code persisted. Since it didn't change with the coil packs changing, would that indicate a wiring issue? The spark checker said the coil was getting power and the ohms for it were normal at 0.7 as were the other coils.

I'm going to pick up a mechanic book to look further into what the wiring harness power should be. It may be the crank shaft sensor I guess, since it now runs after cleaning some grime off it.

It runs now, super rough at first, then it steadies out and reaches 2,000 RPMS, then lowers back to 1,500 but still seems rough. Then it gets even slower like its having fuel line problems, but the pressure is good. Maybe dirty fuel injectors?

Thoughts? Thank you!

 

Have you looked carefully for evidence of rodents chewing on the wires? I worked with a guy in FL that had this happen to his diesel F350. So, it doesn't just happen up north.

 

The fact that it starts and runs does tell you the injectors are pulsing.

Have you changed the fuel filter?

 

No signs of chewed wires or rodents living in the truck.

I'm going to check out the fuel injectors tomorrow and clean/replace them. I think I will also replace the ignition coils and spark plugs. If it solves the problem then that would be awesome, and if not then it will still make for a better engine.

I have not replaced the fuel filter but the pressure is good. Would that be beneficial to replace based on the engine problems?

Also, what would be a good compound for cleaning fuel injectors manually? I don't want to use something like carb cleaner since the injectors are plastic and may be damaged.

 

Fuel filters should be changed every 30k. You may have contaminated gas.

Use Motorcraft SP546 spark plugs and Motorcraft, Denso, or Delphi coils. Use high temperature nickel antiseize on the ground barrels, don't get any on the electrodes. Be aware of the sticking and breaking issue, have a Lisle extractor tool available if any do. Use dielectric grease in the coil boots.

Either get rebuilt/new injectors or throw a couple bottles of Techron in the gas. They can only be properly cleaned on a flow bench.

 

It will be a few weeks before I have the next update. Amazon deliveries for a few items are backed up due to the virus.
The ignition coils and fuel injectors came out easy and the spark plugs were aftermarket, thankfully, so they came out in one piece.
I will be replacing the coils, spark plugs, fuel filter, crankshaft position sensor, throttle position sensor, and clean the injectors with a little DIY kit.
If it's the PCM or some other advanced problem, then at least it'll be a smoother drive to the mechanic shop as opposed to the tow I would have needed before troubleshooting!

 

Update:

Alrighty so I replaced the spark plugs, ignition coils, the TPS, and the fuel filter. I also cleaned the fuel injectors.

The codes went away but the truck does not run well enough to drive. Before all this work it had a super rough idle (if it even started) and barely stayed alive. Now it has an amazing sound and better idle, along with a lot less engine shaking, but it won't idle unless I give it a lot of gas. Then, when idling with a good bit of gas, it will sputter out a little and need more gas to come back to normal but sounds like it wants to backfire almost. Some white smoke comes out of the exhaust and, I think, the exhaust manifold.

Truthfully, I'm not sure what to think anymore. Other forums suggested all kinds of stuff and more complex mechanical fixes. Currently it seems like the valves may be sticky or something of that sort but that's out of my league. I truly appreciate the time and effort from everyone on this site but I'm going to get it towed and hope for the best.

 

Time for a compression test.