Codes PO300, PO301 and PO303, Engine Misfire?

Tiny
OREO101
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  • 2005 FORD EXPEDITION
  • 5.4L
  • V8
  • 4WD
  • AUTOMATIC
  • 200,000 MILES
Hi,

Let me ask you for your expert advice.

OBD II scan showed these DTCs.
PO300
PO301
PO303

As you know, these are engine cylinder misfire.
I have the Ford 5.4L Triton.
with the Dreaded spark plugs that can break off in
cylinder head.
I see many YouTube videos showing ways to minimize breakage.
One guy ran, in steps, six cans of seafoam through the gas tank to try to clean out or minimize carbon buildup.
And then he carefully loosened each plug 1/8 turn then poured more seafoam around plug so it seeped down around threads, then tightened back 1/8 turn.
Then repeated this process until he can safely remove plug.
What do you think?
Wednesday, September 21st, 2022 AT 1:08 PM

14 Replies

Tiny
JACOBANDNICKOLAS
  • MECHANIC
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Hi,

The idea of working the plug a small amount both out and back in is a very good idea. It helps eliminate dirt from building up on the spark plug threads. However, once you turn it the first 1/8 turn out, make sure to lubricate it with penetrating oil before moving it again. Allow the oil to sit for approximately 10 minutes before turning it again. Also, the engine should be warm to the touch, not cold or hot when this is done.

The most important thing is to use a good penetrating fluid to help dissolve corrosion and lubricate.

I have used several good products such as PB blaster, liquid wrench, WD40, and Sea Foam Deep Creep penetrating oil, and all are good. The best one I ever used was sold by CRC and is called freeze-off. See pic below. You may want to consider trying it.

I attached information below related to a technical service bulletin. It explains what to do to remove them. Also, it includes the directions in the event one breaks.

Let me know if you have other questions.

Take care,

Joe

See pics below.
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Wednesday, September 21st, 2022 AT 9:01 PM
Tiny
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Hi Joe,
Thanks for your help!
I will get the Freeze-Off.
What do you think about adding all that seafoam to the gas tank? Would that really help to remove carbon since the area where the spark plug breaks is on the outside of the cylinder, correct?
Or should I just use the method we discussed where I loosen the spark plug 1/8 of a turn then added penetrant wait 10 min then tighten then proceeded until the plug is removed and hopefully not broken. I think I will buy the remover tool just in case the plugs break off just to cover myself.
Thanks again,
Greg
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Friday, September 23rd, 2022 AT 8:20 AM
Tiny
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Greg,

The plug can break right where the threads begin. The procedure you mentioned is exactly the same as the technical service bulletin I found. So, yes, I would follow those directions.

The freeze-off is an interesting product. When it's first applied, it lowers the temp of the bolt (I have no idea how) which causes it to contract breaking rust. I have had a lot of luck with it. It's funny, I was replacing the struts on my truck and cannot get the lower mounting bolt off and guess what I'm out of. LOL, I don't like it, but I have a feeling I will need torches to burn the bushings out. Ugh!

Let me know how things work out for you. Also, I do feel running an additive in the fuel tank is a bit over the top. Just take your time. Don't try turning it out without working it back and forth.

Take care,

Joe
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Friday, September 23rd, 2022 AT 8:27 PM
Tiny
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Good luck with the strut job!
I will let you know how it goes!
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Monday, September 26th, 2022 AT 2:41 PM
Tiny
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I noticed I haven't heard from you for a couple of days. Any progress? Just curious. The struts are still in the box. No time. LOL

Let me know how you're making out.

Joe
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Wednesday, September 28th, 2022 AT 4:53 PM
Tiny
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Hi,

Sorry for not getting back to you. I used PB Blaster to penetrate instead of Kroil. Kroil is expensive. It gets great reviews on Amazon. Is Kroil really superior to other penetrants? I was going to use FreeeOff but was thinking.
Would FreezeOff being cold cause any problems when sprayed onto warm spark plug? Also, I was going to use CRC Dielectric Grease. See image.
No silver in it but it looks good.
What do you think?
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Saturday, October 1st, 2022 AT 8:48 AM
Tiny
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I repeated last post. My bad.
So, the plug I pulled out was E3 brand.
See images
Does this mean I don't need to worry about
breaking off top of plug?
Or are these E3 plugs 2 piece also?
They have about 100,000 miles on them.
Thanks!
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Saturday, October 1st, 2022 AT 12:31 PM
Tiny
JACOBANDNICKOLAS
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Hi,

As far as the plug, regardless of what is there, take your time and act as if it can break off. Also, the freeze-off would have actually worked better if the engine was warm. LOL However, what you used is also good and worked. That is what is important.

The CRC is really an electrical connector grease. It is good to use in the spark plug boot. Is that where you plan to use it? If so, yep, it's fine. I have the same can in my toolbox. LOL

Let me know how things turn out for you or if you have other questions.

Joe
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Saturday, October 1st, 2022 AT 3:10 PM
Tiny
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I was wondering why TSB does not recommend antiseize grease on threads of spark plug? I thought that is where you would
normally put antiseize grease?
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Monday, October 3rd, 2022 AT 8:19 AM
Tiny
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It is really based on the spark plug design. If you have plugs that are shiny steel, they are designed to do the same as anti-seize. If the threaded portion is black carbon steel, then you can use it. However, only use a very small amount.

Also, keep in mind that the CRC dielectric grease won't hold up to the temps it will see. If you use anything use anti-seize.

I hope that helps. Also, how are things going? Have you been able to remove all of them?

Joe
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Monday, October 3rd, 2022 AT 8:24 PM
Tiny
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Only the 1. I am waiting for the rain to end.
Remnants of Ian:(
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Tuesday, October 4th, 2022 AT 11:17 AM
Tiny
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Hi,

I understand. I'm north of FL. I have seen what they are faced with. Wow. I wish I could physically go there to help. I really feel bad for the people.

We already had the remnants of the storm. Regardless, when you can, let me know.

Take care,

Joe
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Tuesday, October 4th, 2022 AT 7:09 PM
Tiny
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Yes, that must have been crazy in FL.
I feel bad for the people who lost loved ones.
And lost their homes, etc.
I had success replacing spark plugs!
Thanks for all your incredible help.
I am now going to open another question post.
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Wednesday, October 12th, 2022 AT 3:16 PM
Tiny
JACOBANDNICKOLAS
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Hi,

Thank you for the update. I'm glad to know you got them out. I will watch for your new post.

Take care and let us know if you have questions in the future. You are always welcome here.

Joe
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Wednesday, October 12th, 2022 AT 6:36 PM

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