This has been an occasional issue since I purchased the car in March. Just to recap I've had the entire timing chain components replaced, then ECU re-timed to sync mechanical and ECU timing. I've had an $800 dollar carbon cleaning, performance is great except for the strange occasional ping or pings mostly in third gear. If it were the HPFP I'd get a Cell. I will admit that since I went from the stock CAI to the AEM CAI, that the frequency and intensity is more pronounced with the AEM CAI but this issue still occurred even with the stock CAI.

I use Shell V-Power 91 exclusively as my Mini runs well on it. Could it be the gas quality, perhaps but then why aren't others complaining of the same issues? My gut tells me that the cause is a lean event, meaning that at times it seems like I'm running just a bit on the lean side. The increase in air volume might be making things leaner since more air is entering into the engine because of the AEM CAI, it's all speculation at this point. It would be nice to finely solve this debacle! Dealer can't find anything wrong with it, so this is where I'm stuck! Gas miles are 27 city and 38 highway.

 

As a test, try and get higher octane and see if it still happens.

 

You mean an octane booster? I can get 110 octane in a large gas container, but not directly into the tank as that's illegal in California. I think 110 octane would be way too much though. Is there a way to see if one of my O2 sensors is bad by measuring the resistance when cold and hot? I did this on my 87 Toyota GTS when measuring the O2 sensor when cold and hot, it was out of spec.

 

Everything is illegal in CA.

Actually I didn't know if 91 was the the highest that you could normally get. Do you have a way to monitor you AFR and other stuff? Like with the torque or dashcommand app?