Engine " P0316" Engine Misfire First 1000 Revolutions.

Just wondering. What have you done to rule out a loose CKP sensor?

How about the crank damper? Under drive pulleys? How was the crank damper torqued?

Another possibility is loose/worn timing chains.

If clogged injectors are suspected, consider a cleaning flow test service such as injectorRX.com.

Groundshaker said:

I am an old man that has let progress get way ahead of me.

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How old are you anyway? Too old to learn? You must be young at heart if driving two 2002 GT Mustangs! I'm knocking on 60's door myself. So I suspect we are more similar than different. I grew up driving cars with carbs and points.

One of the differences in my case is a Ford reference library to study and learn from. If interested in getting a copy for yourself I maybe able to help. PM (that's private message) if interested.

A small investment in reference materials might save you 1,000's allowing you to keep the cars that you have and not spend $$ on an old car just because of being behind the learning curve. The new cars really are better in terms of safety/reliability if one is honest.

Groundshaker said:

I have no idea what a CKP sensor is.

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CKP = Crank shaft position sensor. This is the sensor that tells the PCM where in the rotation the crankshaft is. This lets the PCM know when to spark and to inject fuel. Think of it like a distributor/points/PIP (depending upon how far back you want to go).

Groundshaker said:

Could the code (listed above) be a weak coil?

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IF the COP coil was weak, it would be weak all of the time not just in the first 1000 revolutions. In my experience this DTC code is usually associated with a motor base timing problem.

Hence one of the reasons I was asking about the crank sensor and crank damper. Note, sometimes cheap under drive pulleys can cause an unstable CKP sensor signal.

Groundshaker said:

I just read it and got a different code from before (lean condition in bank #2). < that is the before code. Now it says misfire.

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Always post the full DTC codes. There are 1,000's of them and they each have a story to tell.

But as an reminder. For a lean related DTC the odds favor a vacuum or exhaust leak.

As a parting point, This problem could be something as simple as a loose screw holding the CKP sensor to the block. A 5 minute fix including the time to get the tools out.

Nor did you answer the question if this car has under-drive pulleys. Often people "mod"ing their own cars focus on the $$'s when swapping parts. Cheap under drive pulleys or incorrectly installed crank damper pulleys can CAUSE an unstable CKP sensor signal. A stock crank damper is a $65 part with an hour of install time. So even if you have to pay to have the work done is cheaper than selling. And even if you still decide to sell, it will pull in more $$ if working as it should.

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What you could be experiencing is the "dark" side of user "modding". There really is a reason why Ford designed certain parts the way that they are. Poorly designed cold air kits that cause drive-ability problems. Already mentioned under drive pulleys and the problems they can cause.

Of course this car may have bigger issues such as worn timing chains. Someone out in Internet land could possibly know without more tests.

Sorry we couldn't bring you into working/fixing a modern car. Good luck to you.