P0303, cylinder #3 misfire.

[ORRadtech]

Swapped coil packs, still on #3
I'll check plugs next. At 76k+ miles it shouldn't need new but they won't hurt.
Next will be checking injectors. I've put some cleaner in the tank to see if it helps.
I've looked but can’t really see how to get to the injectors. I'm assuming the intake has to come off, yes/no?
Any thing else I should be looking at?
Any good you-tube videos on injector removal?

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[Scootsmcgreggor]

Losing any coolant? Keep a very close eye on coolant level. If you’re losing any it’s likely the head gasket. These motors can blow the gasket between the cylinders. Small leak at first that can grow with time. You can also pull the plug to see if #3 looks different than the others. If you have a tuner you can watch ignition correction value and across cylinders and see if #3 tires s advancing on par with the rest.

Do you get the misfire or rough idle at startup?

 

[Fx2beast]

Swapped coil packs, still on #3
I'll check plugs next. At 76k+ miles it shouldn't need new but they won't hurt.
Next will be checking injectors. I've put some cleaner in the tank to see if it helps.
I've looked but can’t really see how to get to the injectors. I'm assuming the intake has to come off, yes/no?
Any thing else I should be looking at?
Any good you-tube videos on injector removal?

Do a compression test make sure the cylinder with the misfire issue has the same compression as the rest of the cylinders. If you did coil and plug only other thing would be compression or possible carbon build up blocking a injector. Could be a pcm issue but that's a low chance.

 

[Scootsmcgreggor]

Just know that a compression test and even a good leakdown result may not mean that the head gasket has full integrity. I was losing coolant and my hg was blown but compression and leakdown were both good.

 

[Fx2beast]

Just know that a compression test and even a good leakdown result may not mean that the head gasket has full integrity. I was losing coolant and my hg was blown but compression and leakdown were both good.

A compression and leak down test doesn't always point to a blown head gasket.

 

[Fx2beast]

A blown head gasket is actually very easy to find without needing a compression or leak down test.

 

[ORRadtech]

Thank you gentlemen for the ideas, even though it's not what I wanted to hear...

I'm at somewhat of a loss right now. When I stopped troubleshooting it yesterday it was still showing the code. This mornings start up was smooth and the CEL is gone like it never existed. I don't know what to think? I've never had a misfire code just dissappear.
To compound my anxiety, I take it to the body shop today to fix where it got rear ended so I won't have it back for a week or so...

 

[ORRadtech]

A blown head gasket is actually very easy to find without needing a compression or leak down test.

Mind sharing that process please?

 

[Fx2beast]

Mind sharing that process please?

It takes those exact service tools. The compression tester will check just that the amount of compressed air in the cylinder hole. If compression is lower than specs required then a leak down test is required which also requires a leak down tool. There will be shop air applied to cylinder while it's on compression stroke and it will tell.ypu if there's a leak. Depending in where you find the leak will tell what's failing.

 

[CJJon]

Thank you gentlemen for the ideas, even though it's not what I wanted to hear...

I'm at somewhat of a loss right now. When I stopped troubleshooting it yesterday it was still showing the code. This mornings start up was smooth and the CEL is gone like it never existed. I don't know what to think? I've never had a misfire code just dissappear.
To compound my anxiety, I take it to the body shop today to fix where it got rear ended so I won't have it back for a week or so...

Better tell the shop - and get in writing - to not drive the car. Mention a possible engine issue that may get worse and blow the engine with hard driving. If they need to test drive for some reason, require you to be along on any ride. Get that in writing too.

Did you pull the plugs yet?

 

[velocity550]

All this talk about a blown head gasket when it could just be a simple spark plug lol. I'm hoping you put 93 or 91 octane in it correct? If I were you I'd pop a new spark plug in it because that's the cheapest option so far.

 

[ORRadtech]

As above, CEL is currently off.
I will change all 4 plugs, because why not, when I get it back.
I always run 93 unless it isn't available.

The head gasket worries me mostly because my luck has been in the crapper the last few weeks...

 

[Fx2beast]

All this talk about a blown head gasket when it could just be a simple spark plug lol. I'm hoping you put 93 or 91 octane in it correct? If I were you I'd pop a new spark plug in it because that's the cheapest option so far.

I mean if it's a shop looking at it I would hope that's the first thing they check . I gave him a worst case scenario.

 

[Fx2beast]

It's pretty simple let the tech take care of it!

 

[Fx2beast]

As above, CEL is currently off.
I will change all 4 plugs, because why not, when I get it back.
I always run 93 unless it isn't available.

The head gasket worries me mostly because my luck has been in the crapper the last few weeks...

A head gasket is more than likely not it! You would be dealing with over heating issues or coolant & oil mixing. You can check those fluids to be sure. On these ecoboost biggest issues is piston rings frying, turbo bearings, sticking valves. I work at ford so we see it often. Most is turbos failing to the point with oil consumption resulting in engine failure.

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