I have codes po170 & po173 which reads fuel trim malfaction bank 1 & 2.
I just replace the mas air flow sensor the whole thing .
Can someone tell me, where to look, where bank 1 & 2 are.how to fix.
I thought fuel trim had something to do with mass air flow.
Any help thanks.

 

Looking for coorect fix have a 99 E320 with code po170 po173

 

I have a 99 E320 with code po170 po173 I changed the upstream o2s and fuel filter and cleaned mass air flow and found no vaccume leaks and have same problem can someone help thanks