Just bought an 87 300e. It has a smog problem I'll post about later, after I've spent some time checking things I found on other threads here. (Love this forum!)

However, just a couple of quickies.

1. Under the front passenger carpet there are two things I don't understand.

1. A black box with a multi-pin connector. Bosch audio component I think - but what is it?

1. Another small red box, possibly a connector cover? Could this be the 02 sensor's connector?

2. The fuse for the front right / left rear windows blows repeatedly. If I short the fuse connections, the windows perform normally. Put a fuse in, it blows instantly on pressing the window switch. Any tips?

Thanks in advance!
tjh

1) The oxygen sensor connector is in black box...consists of 2 prong (heater) and 1 prong (signal).

2) Look in the left rear rubber housing from the door to car body for frayed and shorted wires... this is a most likely location... that is easier to check than the front right door. When I had similar symptom (opposite doors) that’s what it was.

Edit: about your smog problem I am having same.
PA Emissions -Failed
but I cant deal with it until some parts arrive:
The best thing that ever happened to her?

There are lots of good threads for our car (early 300E's) search emmisions.

__________________
-Marty

1986 300E 220,000 miles+ transmission impossible
(Now waiting under a bridge in order to become one)

Reading your M103 duty cycle:
http://www.peachparts.com/shopforum/831799-post13.html
http://www.peachparts.com/shopforum/831807-post14.html