P0300, P1130 and P1135

[OpticNerve]

I have a 2000 Avalon with almost 158,000 miles. About three weeks ago my Check Engine etc. lights came on so I pulled the codes and get P0125, P0300, P1130 and P1135. Researched the codes and decided to pull the Bank 1 Sensor 1 Air/Fuel Sensor. Got good info with pictures from this forum and a great guy who calls himself Richpin06 over on you tube, helped me find the little rascal way in the back down low. Thought I needed to buy a special socket, but Rich showed that a 7/8 combo wrench will do the trick. After 30 minutes of trying to disconnect the connector, and getting a grip on the sensor, I finally got it out. Lots of carbon and no resistence told me I had one of the causes of the codes, so I took the part number 89467-41030, found a genuine Toyota parts web site, and ordered it.
A week and $175 later, I get the part and put her in. All seem fine initially, but three miles down the road the lights all come back on. Now I get one of the same codes P1130, and some new codes P0171, and P1150. So the ECM is trying to tell me that it still does not like the Bank1 Sensor 1 (Air/Fuel), it's running lean, and depending on what web site you look at and who you believe, the ECM does not like the signal voltage from either the Bank 1 Sensor 2 (post cat O2), or the Bank 2 Sensor 1(air/fuel sensor in exhaust manifold near radiator). I went down to the dealership and got the Bank 1 Sensor 2 89465-07040 $145.00. Not easy to get the seat up and the connector disconnected or the sensor out from the exhaust pipe. Got her done, clear the codes, took her out and boom the Check Engine etc, all come back on. Check the codes and now get P0171 and P1150. So I figure, what the hell, might as well change the Bank 2 Sensor 1, air/fuel sensor 89467-41040 $175 and the MAF sensor 22204-07010 $138.00. Week goes by, put them in, and so far no DTC's or Check Engine lights. I may not have needed the post cat O2 sensor, but I have read that mixing new and old (10yrs 158k) sensors creates out of synch conditions and the ECM throws out all kinds of DTC codes. Could have saved buying direct from Denso, but did not want to play around.