Got Knocking Pinging Popping? Do The .22 Mod
I have an 09' with 18K miles and since about 8K miles I started to experience pinging during acceleration or pre-detonation of fuel and popping/light backfiring when the throttle is closed at a roll in gear. I cleaned the air filter, tightened the exhaust bolts, checked timing, changed plug, decarbed the engine with seafoam, and ran seafoam through the carb but nothing worked.
As time went by it became worse so I started to just use 91 octane which cured the pinging but not the popping. I did lots of looking on web and there are lots of you out there with the same issues. The solution is the .22 Mod. Did mine yesterday and all problems are gone and the throttle response is incredible. If you don't know what it is do a search or look at the vid on youtube.
Strange thing is that when I drilled out the pilot mixture screw cap and tried to turn the screw in it was already bottomed out and would not turn in at all. I have been riding it this way since it left the factory but no symptoms of a lean mixture until 8K miles. Anyway hope this helps.
BTW, the #4 washer (mentioned in the vid) at Ace Hardware is too large to fit tight on the needle and inside the plastic spring seat legs. I had some tiny washers and one fit just right. The washer should be about the size of the needle head.