1993 f-159 with 1988 5.0 with no pollution stuff
fuel injected. here's the problem.
starts fine and idles great for about 5 minutes , check engine light comes on and it very nearly stalls at which point it begins to miss and surge and basically tries to die.
if i feather the Throttle i can keep it running but not smooth!!
cAN'T FIND AND VACUUM LEAKS AND THE EGR SEEMS TO BE WORKING(PUSH PLUNGER UP - TRK. DIES.
RAN FINE WHEN I BOUGHT IT THIS WAY ABOUT 1 YEAR AGO AND ALL OF A SUDDEN THIS.
NOTE.... IT STARTED DOING THIS AFTER IT RAN LOW ON COOLANT BUT DID NOT OVER-HEAT.

PLEASE HELP AS THIS IS MY DAILY DRIVER

 

I would start by scanning for codes.