Car stalls when A/C is on

[oooty21]

I just got my A/C recharged on my 1981 SC (I figured that it would help a bit in the 105 degree weather...). The problem is that when I downshift (dropping into low RPMs), coming almost to a stop or to a complete stop, the oxygen sensor light comes on, and the engine stalls. No issues whatsoever if I turn the A/C off prior to stopping. Any suggestions on what might be happening here? Thank you.

[BMW&PorscheDude]

I had this exact same problem on my 1981 911SC. Ends up I had too much timing. Adjusted it back to stock setting and it solved the problem. Hope this helps!

[oooty21]

I will give stock timing a try. Thank you