Spark plug & cops project
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Joined: May 2012
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From: UTAH
Spark plug & cops project
Hi All! I purchased a 99 F-150 XLT with the 5.4 L Triton Engine from an auction for $2k. Has about 197k miles and runs well until last night when I started hearing a knocking noise while driving and then stalled. Checked under the hood and discovered boot on cylinder #3 is off seat. Decided to tow it back home. Got an OBD reader this AM and gave me P0303 - Cylinder #3 Misfire. Decided to change all Spark plugs and COPS and when I finally got the spark plug from #3 (PITA!), got a surprise! Prior owner (I assume) used an Autolite Revolution HT1 Spark Plug that was inserted in a thread repair insert. Why am I surprised? Well this Autolite was 3.58" long and the recommended Motorcraft plug is only 3" long (see photo attached). To make a long story short...I need advise on how to properly resolve this. My thoughts are to use the proper thread repair insert and use the highly recommended Motorcraft plug. Any insight on how to best and properly resolve my issue is highly appreciated!
99 F-150 XLT 5.4L Engine 4WD AUTO TRANSMISSION
99 F-150 XLT 5.4L Engine 4WD AUTO TRANSMISSION
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Junior Member
Joined: May 2012
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From: UTAH
Spark Plug Thread Repair Kit by Dorman
Found the actual kit used by prior owner/mechanic. It's a Dorman Help! - Spark Plug Thread Repair Kit Part # 42025 sold at O'Reilly Auto. Has anyone used this before in their truck? Can anyone please let me know what will be the better alternative? I don't want to use the same kit and would rather by another thread repair kit but need some guidance as to what is the best thread repair kit for this truck. THANKS! Here's the photo of this kit:
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Joined: Feb 2011
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From: pembroke ontario canada
someone can correct me if im wrong but im pretty sure the plug he has used is for a newer 04+ 5.4l 3v engine not our older 5.4l 2v , so that being said the knocking noise is not good if the plug was too long she could have done some damage ,
not sure if this info is right but i changed the plugs on my sisters 04 fx4 and that plug is identical and i know my 2003 kr 5.4 has totally diffrent plugs
not sure if this info is right but i changed the plugs on my sisters 04 fx4 and that plug is identical and i know my 2003 kr 5.4 has totally diffrent plugs
fxmf4
Joined: Mar 2011
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From: joplin mo
Originally Posted by sledneck666
someone can correct me if im wrong but im pretty sure the plug he has used is for a newer 04+ 5.4l 3v engine not our older 5.4l 2v , so that being said the knocking noise is not good if the plug was too long she could have done some damage ,
not sure if this info is right but i changed the plugs on my sisters 04 fx4 and that plug is identical and i know my 2003 kr 5.4 has totally diffrent plugs
not sure if this info is right but i changed the plugs on my sisters 04 fx4 and that plug is identical and i know my 2003 kr 5.4 has totally diffrent plugs
Thread Starter
Junior Member
Joined: May 2012
Posts: 5
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From: UTAH
someone can correct me if im wrong but im pretty sure the plug he has used is for a newer 04+ 5.4l 3v engine not our older 5.4l 2v , so that being said the knocking noise is not good if the plug was too long she could have done some damage ,
not sure if this info is right but i changed the plugs on my sisters 04 fx4 and that plug is identical and i know my 2003 kr 5.4 has totally diffrent plugs
not sure if this info is right but i changed the plugs on my sisters 04 fx4 and that plug is identical and i know my 2003 kr 5.4 has totally diffrent plugs