Okay, after (2) P0171 last two weeks I finally bought the Electrical cleaner at Autozone. They didn't have the B12 stuff, so I had to buy a different brand.
Monday I put the CTA apart and I brought inside the house the MAF & IAT. I kept cleaning the parts throughout the day. I also cleaned the wire connectors (both on the sensor and on the car side).
Tuesday: I took the train, and I had to drive only 7 minutes top. Funny thing: I go hard on the car and I hear NO PINGING !!!!
Can you believa that ?? NO PINGING !! For the first time EVER !!
I thought the car wasn't warmed up enough, so I keep my expectations low.
Today I drove to work. 20 miles. i step on it and NO PINGING again !!!!
I can't believe it. I didn't even thought about cleaning the MAF and fixing the pinging problem. After all, I've been asking for years about the pinging and NO ONE ever mentioned MAF/IAT sensors !!!!
Is the car playing with me or the pinging is really GONE ????
Does that make any sense ??? Could eitehr the MAF or the IAT be causing the pinging ?????

Later