My '89 Vanagon GL has been running rich. My previous mechanic told me so. I
asked what would make it run rich, and he said he would start by checking
the OX sensor, which had been replaced (by someone else) about 5K ago. He
said it wasn't urgent and left it at that.

I had some personal issues with my previous mechanic, so I took it somewhere
else this morning for a minor service. The new mechanic said what I already
knew: the car runs rich and that it probably wouldn't pass smog. Yet, it
*did* pass smog last month. I asked what should be done about it and again,
he suggested the OX sensor, but he wasn't entirely sure. He recommended
having this corrected to improve my mileage.

On a scale from 1 to 10, how important is this to correct? Like I said, I
had the OX sensor replaced 5K ago. It is a non-stock OXS to be sure, but do
I really have to spend another sh*tload of money to replace it? Could it be
the AFM? And if it is the AFM, isn't that another sh*tload of money.

I'm getting about 215-220 miles per tank in the city (Los Angeles... stop
and go traffic...daily driving).

Please advise.

Love and Rockets,
DaBomb