ok, this has been bugging me for a long time. I had an Injen intke in my 01 GS300 for a few years. I alwas noticed a significant lag once i hit 3400 rpm that lasted through the 4600 rpm range. it was like the car would take off great, then lag, then kick in again. it felt like i took my foot off the gas, but i was flooring it! Anyway, the check engine light came on a while later, and my dealer ran the code and sad it was an O2 sensor. They replaced it, the light went off, then on the way home it went back on. The said that there iare 4 O2 sensors and they can't tell which one it was, so they had to keep replacing them until the light stayed off. I didn't want to pay, so i just drove it that way for a long time. This past week, I put my stock intake back on, then the lght went off! for good!! the dealer ran the code in memory and there were 2 of them, one was the intake temp, and the other was the MAF. Either way, they said it's all clear now and the light isn't on so it must have been the intake that messed it all up. Now, the car does drive better, but i still notice the lag a little bit. Is ths when the VVTi kicks in? If i pull the fuse or battery terminal, should this reset the ECU and fx the lag issue? Has anyone had ths happen or heard about it? I did try to search before asking, so i'm sorry if this has come up before. I really don't want to take it to the dealer and pay the fee for "dagnosis" then repairs. HELP! I'm about to get the car supercharged and i want to make sure that it's running right before I do that.