O'Rattlecan
Redneck Prognosticator
Well I didn't post up about the issues I was having about my 5.4L until I had a resolution and I had some other issues cooking that muddied the waters making my problems harder to diagnose, but here it goes.
In my 2005 F150 with the 5.4L, I developed an engine shudder while driving down the highway. I thought it was a bad coil so I swapped in a new coil and put a new plug in there just to be sure it wasn't soaked in gas and ruined. It got better for about 50 miles and suddenly got much worse...
All of the sudden it was shaking pretty violently compared to how it was before. It was coming to sudden stop when I tried to start the motor like it was locked up.
Long story short, my injector failed, it hydrolocked, and I bent the rod on cylinder #6. After all that work was done, I instructed the mechanic to go ahead and use the Champion plugs because they avoided the 2-piece design that Motorcraft had for their spark plugs. The Motorcraft versions have a critical design flaw and are highly prone to breakage while pulling them out of the head.
Knowing full well that deviating from the recommended Ford part could cause me some headache, I decided it was worth the gamble to go with a plug that was re-engineered to NOT break when/if I decide to take them out. I figured if it failed, I could at least swap in some Motorcraft parts without fearing of the plug breaking when I take them out. The Champions ran about $18/plug, while the Motorcraft (SP 507) ran $8/plug.
I got the truck back after the rod was replaced and the mechanic went ahead and swapped my new plugs in. Two of the Motorcraft plugs broke off (the back cylinders #4 and #8) even when following the instructions in the Ford issued TSB 06-5-9. Perhaps Vince can post the TSB for us to help people who are on the internet searching.
Anyway the Champion plugs were a failure. The motor has 139,000 miles on it and it ran terribly with these new spark plugs. I didn't want to jump on here and rag on how terrible they were until I did the swap back to the Ford recommended Motorcraft SP 507 to verify that it was, in fact, the problem. (I did just have a new rod put in after all) The plugs developed a HEAVY miss until the motor reached full operating temperature. Another symptom was rather strange and might be due to the gapping of the plug or the temperature of the spark. This problem was that as the engine spun at faster and faster RPM's, the engine gained no power and even began to lose power past ~2,500-3,000 RPM's. As I took my foot out of the throttle, it improved, but was still not 100%.
I just wanted to be clear that even though Ford truly does have a design flaw with the Motorcraft plugs (originally SP 421, now SP 507), I do not advise replacing it with an after-market plug. Put the Motorcraft parts back in and worry about the headache 100,000 miles down the road when you're ready for your next set of plugs. To help next time, I did apply a little copper-based anti-seize lubricant to the threads.
To be clear, the truck originally came with the Motorcraft SP 421, and the claim is that the SP 507 burns a smidge hotter and helps keep the carbon deposits down on the threads and come out a *little* easier. But the SP 507 is still a 2 piece design.
Hope this helps someone. I couldn't find any one particularly GOOD source of information on the internet and wanted to summarize it myself.
Ryan
In my 2005 F150 with the 5.4L, I developed an engine shudder while driving down the highway. I thought it was a bad coil so I swapped in a new coil and put a new plug in there just to be sure it wasn't soaked in gas and ruined. It got better for about 50 miles and suddenly got much worse...
All of the sudden it was shaking pretty violently compared to how it was before. It was coming to sudden stop when I tried to start the motor like it was locked up.
Long story short, my injector failed, it hydrolocked, and I bent the rod on cylinder #6. After all that work was done, I instructed the mechanic to go ahead and use the Champion plugs because they avoided the 2-piece design that Motorcraft had for their spark plugs. The Motorcraft versions have a critical design flaw and are highly prone to breakage while pulling them out of the head.
Knowing full well that deviating from the recommended Ford part could cause me some headache, I decided it was worth the gamble to go with a plug that was re-engineered to NOT break when/if I decide to take them out. I figured if it failed, I could at least swap in some Motorcraft parts without fearing of the plug breaking when I take them out. The Champions ran about $18/plug, while the Motorcraft (SP 507) ran $8/plug.
I got the truck back after the rod was replaced and the mechanic went ahead and swapped my new plugs in. Two of the Motorcraft plugs broke off (the back cylinders #4 and #8) even when following the instructions in the Ford issued TSB 06-5-9. Perhaps Vince can post the TSB for us to help people who are on the internet searching.
Anyway the Champion plugs were a failure. The motor has 139,000 miles on it and it ran terribly with these new spark plugs. I didn't want to jump on here and rag on how terrible they were until I did the swap back to the Ford recommended Motorcraft SP 507 to verify that it was, in fact, the problem. (I did just have a new rod put in after all) The plugs developed a HEAVY miss until the motor reached full operating temperature. Another symptom was rather strange and might be due to the gapping of the plug or the temperature of the spark. This problem was that as the engine spun at faster and faster RPM's, the engine gained no power and even began to lose power past ~2,500-3,000 RPM's. As I took my foot out of the throttle, it improved, but was still not 100%.
I just wanted to be clear that even though Ford truly does have a design flaw with the Motorcraft plugs (originally SP 421, now SP 507), I do not advise replacing it with an after-market plug. Put the Motorcraft parts back in and worry about the headache 100,000 miles down the road when you're ready for your next set of plugs. To help next time, I did apply a little copper-based anti-seize lubricant to the threads.
To be clear, the truck originally came with the Motorcraft SP 421, and the claim is that the SP 507 burns a smidge hotter and helps keep the carbon deposits down on the threads and come out a *little* easier. But the SP 507 is still a 2 piece design.
Hope this helps someone. I couldn't find any one particularly GOOD source of information on the internet and wanted to summarize it myself.
Ryan
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