1981 fiat spider fi runs then dies

[Seezynn]

My 1981 fiat spider runs for a second or 2 only on the cold start injector. I used the fi troubleshoot guide and it led to the double relay and still no power at injectors. Whst should I do

[spider2081]

Did this car ever run?
Are you sure the car's connectors are on the correct connectors of the dual relay? have you counted the female pins in the harness connector and mated them with the dual relays connector that has the same number of pins?
The ground for the dual relay to operate is made through the pins of the ECU. Is the ECU connected when you are testing the dual relay?
I think the female pins in the harness connectors loose their tension more often than the dual relay fails. Do you have male pins to test the drag on the female pins in the connectors?
Do you have a copy of Fiat publication " Spider 2000 Electrical Diagnostic Manual 1980-1981" And have you read the fuel injection section?
Do you have a fuel pressure gauge and have you measured the fuel pressure?
How are you testing for power at the fuel injectors?

[Seezynn]

I didn’t check fuel pressure but. I hear the pump fun and the fpr is new. I followed the fuel injection diagnosis manual and it led to the dual relay. I checked the connections on the relay and none of them are loose. The car was previously running then it just died while driving. Spark is ruled out as the car runs off the cold start injector. Yes the ecu was in at all times unless I was testing the other sensors. The funny thing is that with this car I had a problem and changed the coolant temp sensor and the car ran then the next day this started with it running then dying

[spider2081]

When do you hear the fuel pump running. It should only run when the ignition key is in the "start" position or when the engine is running and air is flowing through the air flow meter. The dual relay has 2 internal relays, one is called the control relay and it should be activated when the ignition key is in either the "start" or "run" positions. This relay when activated by the ignition switch powers the fuel injectors, the fuel pump switch in the airflow meter and the ECU. If your fuel pump is running its hard to understand why the fuel injectors don't have power. Could someone have changed the factory wiring in your car?
The second relay in the dual relay is the fuel pump relay. It is activated when the ignition key is in the "start" position or when the air flow meter's fuel pump switch is closed. This switch closes when air flows through the airflow meter causing it vane to move. So if the engine isn't running and the ignition switch is not in the "start" position the fuel pump should not be running.
How are you testing for power at the dual relay.
Do you have voltage on pins 88z and 88y with the ignition in the "off" position?
Do you have power on pin 86c with the key in the "Start or Run" positions?
Do you have power on pin 86a in the start position?
Does pin 85 trace to ground? It makes its ground through the ECU. So the ECU has to be plugged in for the dual relay to work.
Have you checked the connector on the air flow meter? the car can start and die when the air flow meter is not plugged in,or loose.

[wizard124]

All your TS led to the double relay. Did you change it out with a known good replacement?
Is your ignition switch functioning properly? In "run" do you get the oil and alternator warning lights prior to going to the "start" position?
Recheck the coolant temperature sensor connection.
Check for broken grounds.