R3 Spark plugs 17,500 miles--NOTE Loose plug!!!
 

I began to notice the past few times I took the car out that the engine seemed to be a bit sluggish. Also it would sort of hiccup a few times while the engine was warming up at idle while cold.. So I decided to change the plugs.

Most of the miles are spirited weekend drives and about 2 dozen autocross events since I got the car 2 years ago brand new. Its not my daily driver

With the new plugs in, the engine is much smoother and revs faster. It feels new again!

Whats crazy though, in doing the job, when I put the socket on the #2 Leading plug, it was loose! I went to loosen it with the ratchet and it just spun freely. I took the socket back off and was able to turn it in about half a turn by finger before it got snug. All the rest of them were tight.

I had a feeling something was going to be fishy about that plug because it was the only one that had some oily residue around the plug hole. The new one tightened up with no problems.

Ill put up some pictures for you guys to analyze my plugs. I was second guessing even changing them because it is well before the 30k mark but I'm glad I did now knowing about the loose one, and they definitely made a difference.


#1 L+T

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#2 L+T Note: You can see the oil on the outside of the plug from the leading one that was loose.


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SIIs do have an updated oil metering pump. Shouldn't put that much more out than S1 though.

After fixing dozens of rx8, I can tell u I seen enough plugs not being torque down correctly. I can even turn them with my finger without much effort

I am admittedly guilty of this. Sure does cause some interesting issues (high rpm misfires, fluttering, excess carbon buildup, etc)

I was just most surprised that they were as the factory installed. It was the first time they had ever been out.

My original sparkplugs were suspiciously easy to loosen. I didn't even need a torque wrench to break them free. I wonder if there's something about the unique vibrations inside a rotary engine that causes the sparkplugs to back-out over time?

I once had the engine management light come on about 1000 miles after a dealer service with a plug change. One spark plug was almost out of the block.

I always torque RX8 spark plugs now.

for some rx8, I can turn it with just my finger, it didn't back out, its loose enough to be turned by finger-force but not loose enough for the whole plug to back out.

its funny to see those owner's face expression though. :lol: