1983 Pulsar/Sentra carb, possible swap?

[Citizen13]

Hi all;

I have a 1989 Nissan S-Cargo JDM, which has a 1500cc Sentra engine with carburetor. I understand this engine/carb is same as the 1983 Nissan Pulsar sold here in NA.

Right now I cannot pass the emissions test here in Ontario Canada. I had the problem before, the problem was that the air/fuel mixture solenoid in the carb was at fault. (I bought this vehicle from Japanoid in Vancouver, they swapped a rebuilt carb for me a couple years ago, but now I have same problem, and they are not much help this time). My CO rate is 5%-6%, limit is 1.5%, indicating too rich mixture. I am looking for either a replacement solenoid or carburetor, or I am wondering...is it possible to swap another, more modern carburetor or fuel injection on this engine? I have replaced plugs, O2 sensor, air filter, etc.

Desperate!

Michael Scott
Citizen 13
Ottawa Ontario Canada