Hi Burdy;
I assume that your '89 has the Solex Cisac carburettor. This dual-barrel carb has fixed jets for air/fuel-mixture, as opposed to the needle found in SU and Zenith/Pierburg 175 carbs. The jets might need cleaning though, but they do not wear. And the main valve might need replacing.
Your car should have a mechanical fuel pump. If it is failing, I would expect it to pump less, not more fuel. But the Cisac has two plastic floats which has a tendency to leak when they get old. If they fill up with fuel and sink, they will open the main valve too much and let too much fuel into the bowl.
One problem I had with mine once, was that the bolt that serves as an axle for the choke linkage came loose, causing 1) the choke flap to close and 2) the throttle linkage to lock up with the choke linkage in full throttle position (a "very interesting" experience, particularly with an automatic transmission!). You might want to check if yours is tight, if not you may experience over-fuelling. I seem to remember that the bolt took a 14 mm socket:
Good luck!