p0170, p0101, p1444, p0411
 

Hi, have a 96 c280. I replaced my MAF. This cleared up the symptoms of rough idle, lag while depressing the accelerator. Now about 3 to 4 months later, the symptoms are back. Along with the codes. Also when unplugging the MAF the symptoms continue. Before replacing my MAF when I unplugged it the symptoms went away, that's one of the reasons why I decided to buy a new one. But this time when I unplug the MAF the symptoms stay the same. Any thoughts on how I should proceed?

I had one of these cars and hated to see her go.
Check and replace all the vaccuum lines. The white plastic ones brittle with age.

Who manufacturered the new MAF you installed? It's a shot in the dark, but that part in particular can be really touchy. Ive had more than one "new" one go bad.