Thought I'd relate my experiences today. Maybe you've seen the same/similar? My Check Engine light has been blinking on and off for bank 5-8, and then stayed on steady. I occasionally noticed a slight misfire when the light would come on. I consulted the posts here, which were most helpful (THANKS all), but here's what happened today. I pulled the codes from both banks and found codes 1111, and 1211 on the 5-8 bank ECU. I found code 3333 on the 1-4 bank (which is supposedly meaningless, or no code), but that light had never turned ON. I proceeded to clear codes in both banks using the switches on the ECUs. I checked signal output voltages on the MAF sensors with a scope and all seemed normal (just < 4.5V on a WOT pulse). I removed and cleaned both MAF sensor connectors, and both ignition coil connectors. None should excessive corrosion or problems. I cleared the codes, disconnected the battery, let the vehicle set 10 min, then reconnected and started it and let it idle for 10 min. All Check Engine lights were out. I turned it off, put the tools away, and then took it for a test drive. It ran great, no issues. BUT, during the test drive, the Check Engine bank 1-4 light blinked ON and OFF (especially under hard acceleration). The original problem, Check Engine bank 5-8 did not resurface? Prior to "fixing" this, Bank 1-4 had been OK? I decided to stop for the day. I plan to go back and clear Bank 1-4 ECM again tomorrow, and try it again? My MAF sensors are Bosch 0280 213 012's, but DO NOT have any adjustment access point visible from the outside (as has been described in other posts). The resistance readings mentioned here in other posts were not the same as mine (way different, like 21K). Pin 6 in my MAFs is NOT CONNECTED on either one. Only 5 pins are active. Pin 1 is ground. Pin 5 is 12V, and Pin 3 is output voltage (4.5V peak under full throttle, normally runs below that value on idle, as viewed on a Picoscope Automotive Oscilloscope). Oh, and FYI, I checked ground at both ECMs housings as compared to the ground pin on the MAF connectors. There was a 0.1V voltage drop....not significant in my opinion. Any thoughts?.....
