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Discussion Starter · #1 · (Edited)
I am throwing a few codes. 203 (cylinder 3 inj okt open), 0316 (startup mis fire), 0303 (cylinder 3 misfire).

Just want to make sure and do the job once. I have a inlet from turbocooker on a 2.1 kb and is a small PITA to take off just to get to the spark plus..

I am thinking it is spark plug or coil. but don't want to replace the spark plug put it all back together to find out its the coil.

Is there an easy way???

Also if I need Coil packs, what ones should I get?

Josh View attachment 83983
 

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Discussion Starter · #2 ·
Pulled out everything and the Spark plug looked fine. So i’m guessing the COP is bad. I think since its already pulled, I might as well replace all the spark plugs. On spark plugs, 1 degree colder is the next higher number? My memory is not all that good and I always forget.
 

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Hate to break this to you. The P0203 DTC is very specific. Bad PCM injector driver.

However, if this were my car, I would Ohm out the injector to PCM return wire to be certain there isn't an open, ground fault, or stray voltage on the line before replacing the PCM.

>>
P0201 through P0212 - Cylinder #1 through Cylinder #12 Injector Circuits

The comprehensive component monitor (CCM) monitors the operation of the fuel injector drivers in the PCM. The test fails when the fuel injector does not operate electrically even though the harness assembly and fuel injectors test satisfactorily.

Possible cause:Faulty fuel injector driver within the PCM.

Diagnostic aids:pID Data Monitor INJ1F-INJ12F fault flags = YES
 

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Discussion Starter · #4 ·
Hate to break this to you. The P0203 DTC is very specific. Bad PCM injector driver.

However, if this were my car, I would Ohm out the injector to PCM return wire to be certain there isn't an open, ground fault, or stray voltage on the line before replacing the PCM.

>>
P0201 through P0212 - Cylinder #1 through Cylinder #12 Injector Circuits

The comprehensive component monitor (CCM) monitors the operation of the fuel injector drivers in the PCM. The test fails when the fuel injector does not operate electrically even though the harness assembly and fuel injectors test satisfactorily.

Possible cause:Faulty fuel injector driver within the PCM.

Diagnostic aids:pID Data Monitor INJ1F-INJ12F fault flags = YES
Ahhhh, shucks.. Now I got to figure out what all that means and how to do it. It is amazing ive gotten this far on my car completing most of the work myself and I still don't know what half of it means..

Thanks WMBURNS, can you explane ohm the injector for me please. It sounds electrical and that alone is scary to me..
 

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PCM=ECU=Computer. Located in the passenger's kick panel.

The hard line is the AC fill port. It's missing the protective cap.

Do you have a set of Ford workshop manuals, wiring diagrams, and PCM manual? This would help you to located the correct wires and connector pin numbers. If interested in getting a copy for yourself, I maybe able to help. PM if interested.

Also handy to know the model year of your car.
 

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Discussion Starter · #7 ·
PCM=ECU=Computer. Located in the passenger's kick panel.

The hard line is the AC fill port. It's missing the protective cap.

Do you have a set of Ford workshop manuals, wiring diagrams, and PCM manual? This would help you to located the correct wires and connector pin numbers. If interested in getting a copy for yourself, I maybe able to help. PM if interested.

Also handy to know the model year of your car.
2003 GT… I Do not have a set of work shop manuals, It would greatly be appreciated If I could find some. I sure wish I started this hobby when I was younger I would hope to be allot smarter about stuff by now.. thanks for the help
 

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Well, the fault stayed with the same cylinder, so I would first do what wmburns suggested. FWIW I believe "ohm out" is wmburns-speak for just doing a continuity test on the wiring. More specifically, use a meter to trace out the #3 injector wires the entire way to make sure they aren't shorted out, crossed, open at any M/F connectors, or any other possible wiring snags. Then, if your wiring proves out, maybe see if you can get your hands on a spare PCM temporarily that you can flash with your tune and see if the issue resolves.

Oh and on one of your earlier questions, I think the plug range will differ per manufacturer, so you'll just need to look up whether a specific plug is "1 range colder than normal" or "2...." etc. For example when N/A I ran NGK TR-55, but one range colder for the supercharger is the TR-6.
 
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