Judging spark plug age
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From: Central Minnesota
Judging spark plug age
Changed out the plugs today on 2010 screw 5.4. Bought the truck last June with under 90,000 miles. Dealer said plugs were not original but I'm thinking not.
The old plugs are HJFS24FP. They look tired and all of 90,000. Plugs show compression leakage.
I don't know when the plugs turned into SP509s, but is it safe to assume I replaced originals?
BTW, easy job for anyone reluctant to take on replacement. I blew out a lot of grit. I could have let spray helper work longer but otherwise plugs came out OK. Regular short and long extenders.
The old plugs are HJFS24FP. They look tired and all of 90,000. Plugs show compression leakage.
I don't know when the plugs turned into SP509s, but is it safe to assume I replaced originals?
BTW, easy job for anyone reluctant to take on replacement. I blew out a lot of grit. I could have let spray helper work longer but otherwise plugs came out OK. Regular short and long extenders.
Last edited by ifallsron; Apr 15, 2017 at 09:33 AM. Reason: additional info