I have a 1987 bronco ii with a 2.9 engin. When it is warmed up it looses power and dies. after about 10 minutes it starts up again but soon dies. whats up with that?

Check your Fuel Pressure.

i would take the ground wire loose from engine and clean it. i seen one before that lost ground and wouldnt start

Sounds like a classic fuel pump failure.

oxygen sensor.

Replace your fuel filters.

check engine coolant temperature when it gets warmer, or at operating temperature, and verify that the temperature gauge is showing warmed up to operating temperature. If the coolant temperature sensor tells the computer the engine is cold it will over fuel and miss and the engine will die. When cooled down it will run fine until it warms up. Also could be coil if it starts missing after warmed up.

replace you duraspark box, when it warms up it shorts out causing the engine to lose fire and quit.

fuel pump

sound like ignition module problems.it act up when engine is warmed up.

check the i.a.c. (idle air control) valve near the throttle body, it fixed my low idle!