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Po 303

  #1  
Old 11-08-2018, 09:44 AM
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Po 303

Truck ran great last night. This morning started up fine backed out driveway then running rough as heck and code PO 300 came up then after I cleared that PO 303 only... Just pulled the cop and plug. Swapped out the cop with a known good one and still same issue. Checking Evap canister purge valve next, then changing fuel filter. EGR system ? where is that on a 2005 5.4?
My service manual says it could be:
  • Ignition system
  • Fuel injectors
  • Running out of fuel
  • EVAP canister purge valve
  • Fuel pressure
  • Evaporative emission system
  • EGR system
  • Base engine
 
  #2  
Old 11-08-2018, 11:28 AM
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It doesn't have EGR, it uses variable cam timing instead.

I'd suspect the injectors - the 2005 5.4 had a bad batch from the factory.
 
  #3  
Old 11-08-2018, 12:58 PM
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Originally Posted by glc View Post
It doesn't have EGR, it uses variable cam timing instead.

I'd suspect the injectors - the 2005 5.4 had a bad batch from the factory.
I didn't think I had the egr, thanks.

The injectors were replaced a while ago. New spark plug and known working cop going on #3 cylinder.
Purge valve seems ok did resistance check.
 
  #4  
Old 11-08-2018, 01:06 PM
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If #3 is still missing after plug and cop swap, swap an injector.

Still bad, do a compression test.
 
  #5  
Old 11-08-2018, 01:10 PM
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Will do.
 
  #6  
Old 11-08-2018, 03:02 PM
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PO 303 is gone. It is still doing the same thing. I start it up, runs ok, when idle comes down starts running rough as soon as it warms up a little... and now I have DTC P2196 Rich bank 1. Maybe injector stuck open? #3 plug was not wet....
 

Last edited by nu-supercrew; 11-08-2018 at 03:12 PM.
  #7  
Old 11-08-2018, 05:38 PM
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P2196 Ford:

Possible causes

  • Faulty Front Heated Oxygen Sensor Bank 1
  • Front Heated Oxygen Sensor Bank 1 harness is open or shorted
  • Front Heated Oxygen Sensor Bank 1 circuit poor electrical connection
  • Inappropriate fuel pressure
  • Faulty fuel injectors
  • Intake air leaks may be faulty
  • Vacuums leaks
Have you checked your FPDM for corrosion? You need a scanner to monitor fuel pressure.
 
  #8  
Old 11-08-2018, 07:02 PM
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Originally Posted by glc View Post
P2196 Ford:

Possible causes

  • Faulty Front Heated Oxygen Sensor Bank 1
  • Front Heated Oxygen Sensor Bank 1 harness is open or shorted
  • Front Heated Oxygen Sensor Bank 1 circuit poor electrical connection
  • Inappropriate fuel pressure
  • Faulty fuel injectors
  • Intake air leaks may be faulty
  • Vacuums leaks
Have you checked your FPDM for corrosion? You need a scanner to monitor fuel pressure.
Just unbolted and checked FPDM, it is intact. New injector for #3 tomorrow night. If that doesn't work, compression test. (?)
 
  #9  
Old 11-10-2018, 01:48 PM
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Replaced #3 injector. Started it up, it ran ok until it starts to warm up a bit and as the rpm comes down it gets rougher and rougher and if I don't tap the accelerator it will stall the engine. Also getting the 2196 DTC.
 
  #10  
Old 11-10-2018, 02:56 PM
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Trying to follow tests from service manual. Not easy when you don't have all the gear. Produced Po 0012 camshaft timing retarded, but that went away and did not store a code.
 
  #11  
Old 11-10-2018, 04:17 PM
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If you've never changed the upper stream O2 sensors, I would suggest doing it using Motorcraft only O2's. Makes a big difference in how it sets up the air/fuel which may be your miss/rough idle. As a maintenance item, they should be changed every 75,000 miles for optimum fuel mileage and performance.
 
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Old 11-10-2018, 04:32 PM
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Originally Posted by Labnerd View Post
If you've never changed the upper stream O2 sensors, I would suggest doing it using Motorcraft only O2's. Makes a big difference in how it sets up the air/fuel which may be your miss/rough idle. As a maintenance item, they should be changed every 75,000 miles for optimum fuel mileage and performance.
That is what I am attempting now. How the heck do you disconnect the upstream on the passenger side?? . I can barely see it, let alone touch it. The sensors have 161k on them.
 

Last edited by nu-supercrew; 11-10-2018 at 04:37 PM.
  #13  
Old 11-10-2018, 10:12 PM
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On the 2004 that I had, it was FAR easier to drop the entire exhaust system at the exhaust manifolds. You can easily get to them when they are on the ground.....or close to the ground anyway. I don't know of any other way to do it. I even had a set of crows foot wrenches and they were of zero value. Once I got the exhaust pipe to manifold nuts loose, it was about a 30 minute job. I reused the donut at the manifold/exhaust pipe as it was like new. FWIW, the nuts on the manifold that holds the exhaust pipe on were not rusty. A little Kroil, wait a few minutes, and used an electric impact wrench. Came right off.
 
  #14  
Old 11-11-2018, 01:28 AM
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If it threw a P0012, your phasers may be on the way out and/or you have low oil pressure at hot idle.
 
  #15  
Old 11-11-2018, 03:12 PM
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Originally Posted by Labnerd View Post
On the 2004 that I had, it was FAR easier to drop the entire exhaust system at the exhaust manifolds. You can easily get to them when they are on the ground.....or close to the ground anyway. I don't know of any other way to do it. I even had a set of crows foot wrenches and they were of zero value. Once I got the exhaust pipe to manifold nuts loose, it was about a 30 minute job. I reused the donut at the manifold/exhaust pipe as it was like new. FWIW, the nuts on the manifold that holds the exhaust pipe on were not rusty. A little Kroil, wait a few minutes, and used an electric impact wrench. Came right off.
Changed out both H02 sensors on the passenger side. Still have the 2196 and had a po 340 for a bit... Idle is high and when it gets down to mid 800's it gets rougher and by low 700's it's struggling to stay running. Swapped out the cam sensor on that side and there was no change. What's left to do? Compression check? I will do compression check this week.
Thanks Lab Nerd and glc for the help....
 

Last edited by nu-supercrew; 11-11-2018 at 05:06 PM.

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