Jaguar Repair: jag xj6, air flow meter, coolant temp

Question
have a1986 xj6 4.2. when cranking car will fire and try to start.as soon as i release the key it dies.noticed that the fuel pump only has power when cranking.any help will be great appriecated.

Answer
Hi Lonnie,
That is true, the fuel pump is activated by the air flow meter. If the engine is cold, a "cold Start" injector sprays fuel into the intake manifold for extra fuel like a choke would do. When the engine starts the injectors spray extra fuel to keep it running by the ECU receiving info from the injection coolant temp sensor.
If the engine dies as soon as you release the key, you need to test ignition power to the coil in the just "key on" position.
Let me know,
Howard