'74 1.8L LJet/fuel pump, Fuel Pump not staying on Options

[RKramden]

This is my first time starting a topic, I don't know if I am even typing in the correct location, but I am having an issue with my '74 LJet and fuel pump. The pump starts with the ignition switch, Pump also runs when Air sensor arm is manually moved. However when starting, it seems that the air sensor is somehow cutting off the fuel pump circuit. The PO had bent the arm so it never opened, but I have bent it back to move as designed. If I disconnect the electrical plug to the Air Sensor, the car starts and runs fine......any thoughts? BTW I have replaced the dual relay, but that did not fix the problem.

[RKramden]

I will check this evening, but I am getting fuel when cranking. If I load it up a little it will start, but it will die when that fuel runs out. With the ignition on, I can move the air flapper and hear the pump run as well. Something appears to be happening between initial start and air sensor opening that is not letting the fuel pump switch over voltage to occur.

[ClayPerrine]

I will check this evening, but I am getting fuel when cranking. If I load it up a little it will start, but it will die when that fuel runs out. With the ignition on, I can move the air flapper and hear the pump run as well. Something appears to be happening between initial start and air sensor opening that is not letting the fuel pump switch over voltage to occur.

Are all the vacuum hoses hooked up per the vacuum diagram? If you have an air leak, especially between the air flow meter and the throttle body, an L-Jet car won't run.

Also, check to see if the big black hose between the air flow meter and the throttle body is split. They are prone to doing that between the folds, and it is hard to see it. Symptoms will be that the car will try to start and immediately die when the engine moves ln the chassis, causing the split to open up.

Clay

[ClayPerrine]

I will check this evening, but I am getting fuel when cranking. If I load it up a little it will start, but it will die when that fuel runs out. With the ignition on, I can move the air flapper and hear the pump run as well. Something appears to be happening between initial start and air sensor opening that is not letting the fuel pump switch over voltage to occur.

Are all the vacuum hoses hooked up per the vacuum diagram? If you have an air leak, especially between the air flow meter and the throttle body, an L-Jet car won't run.

Also, check to see if the big black hose between the air flow meter and the throttle body is split. They are prone to doing that between the folds, and it is hard to see it. Symptoms will be that the car will try to start and immediately die when the engine moves ln the chassis, causing the split to open up.

Clay

Also, replace the oil cap seals. They will cause it to run badly or not at all.