There is not really a set fuel air mixture. Each engine will be different even if they are the same engine during the build process they are set specifically to the engine.
The MAP sensor measures air flow for your car's computer. The computer uses air flow to set fuel flow for the correct fuel/air mixture.
Fuel pump going out throttle body needs replaced air fuel mixture not set right.
Do you mean Oxygen sensor? If so, it measures the air fuel mixture in the exhaust to help the computer set the proper amount of fuel to be added to keep the mixture at the proper level.
Could be that the air/fuel mixture is set too lean. Needs adjustment.
To adjust fuel and air on a one-barrel Rochester carburetor, start by locating the air-fuel mixture screws, usually found on the side of the carb. Turn the mixture screws clockwise to enrich the mixture (more fuel) or counterclockwise to lean it out (more air). For optimal performance, make small adjustments and monitor the engine’s response, aiming for a smooth idle and good throttle response. Additionally, ensure the float level is set correctly for proper fuel delivery.
Check your timing and if it is a carb, check to make sure the air fuel mixture is set properly.
A lean mixture of fuel occurs when there is a higher proportion of air to fuel in the combustion mixture, typically resulting from insufficient fuel supply, excessive air intake, or a malfunction in the fuel delivery system, such as clogged fuel injectors or a failing fuel pump. Environmental factors, such as high altitude or low temperatures, can also contribute by affecting air density. Additionally, an engine's tuning, such as adjustments to the carburetor or fuel mapping in modern systems, can lead to a lean condition if set improperly. This can result in increased combustion temperatures and potential engine damage if not addressed.
idle set too low, adjust the fuel to air mixture on a carb vehicle.if fuel injected, your injectors may need cleaned.Kadius1964~blog me.
To set the fuel and air mixture on a carburetor for a 1400 Nissan, locate the air-fuel mixture screw, usually found on the side of the carburetor. Start by turning the screw gently clockwise until it lightly seats, then back it out to the manufacturer’s recommended position, often around 1.5 to 2 turns. Adjust the idle speed screw to achieve a stable idle, and make fine adjustments to the mixture screw while the engine is running until you reach a smooth idle. Always consult the specific service manual for your engine model for precise settings.
Turn it all the way in and then back out 1 1/2 turns
Turn the fuel screw all the way in, the turn it out two and a half turns. Turn the pilot air screw half a turn in to enrich the fuel mixture and keep it from stalling at low speeds if needed. If the fuel mixture is too lean then turn the fuel screw out a little, like a half turn.