The emmissions test that I have to pass is just for HC & CO at
idle.

I had tried to get everything tuned up my self, but since I don't
have the equipment to measure the gasses, I took it into the
dealer to get it set.

They say I need a new mass flow meter to the tune of us$540.

I know that I can buy one for less, but do I really need one. I must
admit to having fiddled with the spring tension on the mass flow
meter that I have now, but I marked the location of the original setting
and set it back.

TIA,

John-Reed Maffeo '86 Syncro - Glacee