Spark Plug Change @ 61K ( Pic Analysis Needed)

swshawaii · Jul 31, 2011

First change, not too bad considering anti seize isn't used at the factory.

Under two hours using only a universal and boot plier for special tools.

Found #2 & 3 easy to access without removing the liners by climbing in the wheel well.

Concerned with the center electrode wear on 4-5-6. Passenger side has very little.

Possibly from being different type plugs for each bank? Thanks in advance.

[Broken External Image]:

AGSF22PGM / AGSF22PM

Rodger Tellefson · Aug 1, 2011

I'll leave the analysis to others more capable. What plugs did you use for replacement? I changed mine to Autolite XP's with a 0.052-0.053 gap, and they work great.

swshawaii · Aug 1, 2011

Rodger- I used the tried and proven Motorcraft SP500. Old part number AGSF22PP.

Was seriously considering the XP103, price was the same with Autolite's $2 rebate.

The original plugs I removed all came out gapped over.065 and were very tight.

Funny thing is my 2005 Workshop Manual specs the gap at .061-.068. (No hood sticker)

Followed Todd and Eddie's advice of .054. Runs and sounds great.

EddieS'04 · Aug 1, 2011

Steve, they appear to have been firing well. What I do notice is the unusual wear (gapping) for 61K on platinum plugs. I just changed the plugs on Mom's 4.6L mercury @ 100K miles. They were clean and still gapped within spec.

Also The white crusting on the grounds. Can be caused by excess use of fuel additives. Maybe high ethenol pertentage.

The .054 gap is correct. Dont know why your manual says .061-.068. Unless that was for the 5.0L explorer.

Tom Schindler · Aug 1, 2011

You will see different wear on the plugs at opposite sides of the engine. Reason is that when the coil fires, the power goes to one plug, jumps the gap, through the block, jumps another plug gap, and then travels back to the coil.

So, while one spark travels from the center electrode to the strap, the other plug fires opposite. That is why Ford puts 2 different spark plugs on their engines with that type of ignition system.

Tom

Johnny O · Aug 1, 2011

I'd say that for 61,000 miles they look fine.

Caymen said:
So, while one spark travels from the center electrode to the strap, the other plug fires opposite. That is why Ford puts 2 different spark plugs on their engines with that type of ignition system.

Tom

Tom is correct. This is why multiple electrode plugs like the Bosch +2 and +4 do not work well on late-model Fords.