I had these P0170 and P0173 fault codes for some weeks in my car, 2003 3.2 Vectra.
P0170 Fuel trim malfunction (Bank 1)
P0173 Fuel trim malfunction (Bank 2)
I checked that there are no leaks in the flex-pipe from MAF to throttle body. I've searched the web for these codes, and most of the cases these codes (together) are referring to MAF-problems.
I cleared the error codes, and I think that I will try to clean the MAF first with CRC air sensor cleaner, similar to http://www.crcindustries.com/auto/co..._ss.aspx?ID=90
Any other suggestions that I could try? How much these Bosch MAF's cost?