You have a CIS type injection system in that car. The system is all mechanical except for the EHA which has some limited authority to adjust the mixture. The EHA is ultimately controlled by the ozygen sensor thru the Lambda controller module. For the most part the mixture is controlled by the position of air flow sensor plate. The EHA only makes minor adjustments to the mixture. There is no MAP sensor on this engine.
The fact that you smell gas tells me that there is some leak somewhere in the fuel delivery system. Even if the engine was running very very rich you should not smell fuel inside the car. EVER. Lots of black smoke maybe, buy you should not smell raw fuel in the car. Have you checked the fuel pressure regulator?. When the diaphram fails, they leak the fuel into a small vent tube which is connected to one of the breather tubes connected to the valve covers and into the air filter housing. The purpose of this is to vent the leaking fuel to someplace safe, not on the top of the engine manifold. The leaking fuel will be inhaled by engine. If the leakage is high enough, you could get a rich mixture that might cause the symptoms you describe.
You need to locate the source of the fumes. That will most likely point you to the culprit. Check all the fuel lines under the hood. Everything.
The photo I have attached shows the fuel pressure regulator. I am missing the vent line mentioned above. But look for it (green line) on yours. the small tube should go to the crankcase vent tube on the other side of the engine.
I got too many cars!! Insurance eats me alive. Dave
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