GEN 1 Bad Engine Missfire and EVAP Leak

[ChaseA]

Hey Guys,

I have a 2012 with 168k miles, and I took it to get smogged, passed smog, and drove it home with no issues leading up to this. Parked it for the day try and start it the next day, and I have a major misfire with codes p0300, p0305, p0307, and p0316. I tried to drive it around to see if it would smooth out and as I was going down the drive way I noticed my power breaks weren't working and that lead me to believe its an EVAP related issues, I read the forums and it seems the most common missfire/EVAP related issue is caused by the check purge valve.

I took off the check purge valve and it read 22 ohms and I bought this one from oreillys just to see if it would fix it quickly and it also didn't fix anything, but the comments on it say it doesn't work and to buy the OEM?

https://www.oreillyauto.com/detail/c/standard-ignition/engine-sensors---emissions/emissions---air-management/canister-purge-valve-and-solenoid/711fc85bddd5/standard-ignition-2-terminal-canister-purge-valve-solenoid/std0/cp758/v/a/118906/automotive-truck-2012-ford-f-150?pos=0

Has anyone ever dealt with an issue like this before any advice would be greatly appreciated. My wallet is hoping I just need to buy an OEM one and it will fix everything.

 

[Fire Ball]

Check the EVAP hoses, they like to dry rot from the fuel vapors.

 

[ChaseA]

Checked all the EVAP hoses didn't notice anything sprayed break cleaner all over most of the hoses and intake manifold looking for any spikes in RPM and it stayed stable so no signs of EVAP leaks.

Unplugged the coil packs on cylinder 5 and 7 didn't change how the engine ran and the for fun I unplugged cylinders 6 nothing changed then unplugged cylinder 8 nothing changed so basically cylinders 5-8 are down. I also checked the voltage on the coil packs and got 12 volt although I didn't check if there was a signal input. I also checked the fuel injector wires and they were also getting power so I have no clue what is going on with the engine does anyone have any insight? Maybe a short on the cam position sensor leading to it not being detected by codes and causing the PCU to completely cut off spark or fuel on cylinders 5-8?

 

[ChaseA]

Hey everyone, I’ve been troubleshooting a misfire issue on my 2012 Ford Raptor all day and wanted to document everything I’ve tested so far. Looking for any additional insight!

Symptoms:​

• Misfire codes for cylinders 5 & 7 (originally)
• After resetting the ECU, misfire code for cylinder 2 appeared
• MAF sensor code (cleaned MAF and reset ECU)
• Vacuum-powered brakes not working properly
• Engine runs slightly better with the passenger-side catalytic converter disconnected but then runs poorly again
• P0355 Ignition coil E/cylinder 5 circuit malfunction came up today although I already got a 12v reading off it yesterday?
• Using a noid light on every inject they all flashed except on cylinder 5 possible harness damage since the injector isn't getting power and the circuit malfunction code

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Tests and Results:​

1. Cleaned MAF Sensor
   • Engine ran slightly better after cleaning, but the misfire persisted
   • Reset ECU, and a new misfire on cylinder 2 appeared
2. Swapped Coil Packs Between Cylinders 5 & 6
   • Misfire stayed on cylinder 5 & 7, so coils are likely fine
   • Measured coil resistance, all read 0.4 ohms
3. Checked for Vacuum Leaks
   • Sprayed brake cleaner around intake/vacuum lines, no changes in idle
   • No obvious vacuum leaks found
4. Tested Catalytic Converter (Possible Backpressure Issue)
   • Disconnected the Bank 1 catalytic converter
   • Engine ran slightly better, then worsened again
5. Tested Injectors with Noid Light
   • Cylinders 5 & 7 misfiring → Checked all cylinders, cylinder 5 injector with a noid light didn't work
   • No power to the injector!
   • Checked some grounds, all looked fine

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Next Steps (Need Advice On These!):​

Does anyone have experience with injector power loss on these trucks? Could it be a shorted wire, bad PCM, or something else I should check? Any help would be appreciated!

 

[EricM]

If the injectors are not firing on #5 and #7- you need to figure out why.

If there's no voltage to 5 and 7 injectors as you say, it's either damaged wires, or a bad PCM. The PCM drives the injectors and coils.

Check the pins for #5 & #7 injectors at the PCM to see if there is voltage there. If so, find the issue with the wiring. If not, it's the PCM.