An indicator light comes on whenever I start my 91' 100 and stays on for about 1 to 2 minutes. The light is a green number "1" and has an arrow pointing left and one pointing right on either side. Its located just above the Oil Temp. gauge. I've looked through the owners manual and can't seem to come up with an explanation. Does anyone know what this light means???

:-)

Someone had your speedo cluster out, and put one of the light bulbs in the wrong socket. (is there a check engine light?) Take the cluster out, and see that the tape color wraped around the light sockets matches the colored dots on the back of the speedo.

I, too, have a '91 100 and the SAME thing happens to mine...except it's the red airbag light over the oil temp gauge. It stays on for 1-2 minutes after starting and then goes off. I did have the instrument cluster removed by a local Audi dealer several months ago to have the tach light replaced. I wonder if they crossed some wires or bulbs while they were in there? hmm.