2002 Explorer 4.0 eating spark plugs...

[Castle]

Gentlemen,

I have done some searching and haven't come across anyone else who seems to have my problem on the forums.

My 2002 Explorer 4.0 is eating spark plugs. The engine started to run rough around 75k miles so I pulled two of the plugs (one from each bank) and the electrode was pretty much rounded down to a knub on both of them. I went ahead and replaced all of the plugs (gapped correctly to 0.054) and immediately the engine was running great and seemed to have some more power.

About 10k miles later the roughness returned and the engine would buck under 2000 rpms (ran fine above 2000 rpms). I pulled two plugs again and they were rounded down like before. I replaced the plugs again and not surprising almost exactly 10k later (right at 94.5k now) the roughness has returned. I pulled two plugs today and guess what? The electrodes are rounded down again. :thumbdwn:

I will admit I have been using cheapo auto-lite plugs from Wally-World that are like $5 for a pack of 4 (or something like that, either way the cheapos). I should also mention the second time I replaced the plugs I also replaced the coil pack and wires with Ford OEM parts. There is a CEL when the roughness comes but after I replace the plugs it goes away immediately. I think the CEL is telling me the plugs are dead but not what the problem is.

Should I go with a more expensive plug?

Thanks guys.

 

[JDraper]

Try putting a set of platinum plugs in the motor. Use Motorcraft, Autolite or AC-Delco's (NOT Bosch) and don't use any of the gimmick plugs (+2's, +4's etc). The motor is designed to use platinums, not standard plugs.

 

[regalclumbers]

Only platinums should be used. I replaced mine at 50,000 with motorcraft and now have 101,000 and they still look good. I'm going to replace next weekend though.

 

[Castle]

I replaced all the plugs this weekend with Autolite "extreme" spark plugs.

Everything is back to normal, engine is smooth, no CEL. We'll see how long it lasts.