Avensis T22 both banks too rich analysis?

[JS_Toy]

Hello! Tried searching for this but the search function is a bit rough.. 

Have an Avensis T22 2001, 1,8 litre 16v. Error codes bank 1 and bank 2 too rich. Erased them, cleaned out the MAF and they came back again after 2 weeks. 

Read the data now, MAF reading 2,82g at idle (should be normal), 7g at 2000rpm (normal?), O2 sensors 1 (pre cat) on both banks changing as they should, between 0 and 1 v. O2 sensor 2 (post cat) reading 0.69 (bit high or normal?)

Short term fuel trim normal on both banks, long term fuel trims both around -20% (quite high, but not necessarily out of spec?) 

Because the error is on both banks I am suspecting a sensor, either O2 sensors or MAF. Strange thing is that MAF is normal on idle. might it be faulty on higher RPM? 

Is the post cat O2 sensor on this engine controlling the ECU? 

Thanks for any ideas

Cheers from Sweden 

[JS_Toy]

I think we can close this thread... went for a drive and checked the MAF again. It read 3,8g steadily which is too much. Seems like it is the culprit..