The dealer I'm talking to about a 1984 380SL has a number of cars on his lot
and is not too interested in working on this SL for now because it's low
profit compared to other cars.  While this may sound like a dodge, I can
understand this, since in my own business, whenever I have a choice, I
focus on high dollar issues and small projects that could make 1/2 or 1/3
as much often are let go or left on the side for a long time.

Today I took the car out for a test drive. There is almost no rust on this
car. The climate controls even seem to be working, but I wasn't clear about
the AC (didn't turn it on until later). (I know heat/AC is not one of the
biggest issues, but this is one of the few issues I'm unsure of in terms of
repair cost.)  The one issue that could be a deal breaker at this point is
that it's running rich. He says he's checked the injection control unit
(that's on the passenger side, under a floor board, or somewhere near
there, right?) and the warm up regulator. He has not checked the cold start
valve or the injectors themselves.

My first question is about the injection issue. I'm no expert on this, but
if it's running rich, my understanding is that it would either be injectors
(unlikely), the controller, the oxygen sensor, the warm up regulator, or
the cold start valve. Is there more? I know if it were too lean it could be
a bunch of things (rust in the line, pump problems, leaks, etc.), but how
risky is it to get a car like this under these conditions (with two items
checked and not sure what else it is)?

I'll be taking it into another mechanic for a check before I get it. Are
there things they can quickly or easily check to narrow it down? If I could
be sure it would be something below a certain cost level, I'd be much more
inclined to buy this car, since most of it is in great shape. I just don't
want to buy a car with a problem that could grow into many thousands as the
mechanic gets more into it and finds more wrong. Any comments on this
situation, what to look for, what could be checked to rule out some
sources, and so on, would be greatly appreciated.

The other issue is the AC. This is not as big a deal, since I tend to leave
the top down most of the summer, but it would be nice to know about. I had
a 1988 Jeep truck that needed an AC recharge a few years ago and they had
to retrofit the AC to work with the newer gas (instead of freon). If the AC
on this, which I understand worked a year or two ago, needs recharging, is
it a matter of just recharging it, or will it have to be retrofitted
(assuming it isn't)? If it needs retrofitting, is that expensive?

Thanks for any help!

Hal