When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
Hello, Mary, welcome to the forum and congratulations on your C3!
Not sure if you meant to line through your question or not, but did not see that you had posted it in the C3 area yet.
I believe your ALDL connector is under the center console ash tray. However, your '81, unless it has been reworked and modified will only be an OBDI-1 so information is limited compared to newer OBDs.