Went through my 5.0 performed a clean up prior to installing in a kit car. Motor will start for a nano second and then stalls. I have rebuilt the injectors, replaced the F.P.R and replaced the fuel pumb And still motor will not run. Any suggestions on the next positive move towards a running motor.  

Mtn.Cobra:
Went through my 5.0 performed a clean up prior to installing in a kit car. Motor will start for a nano second and then stalls. I have rebuilt the injectors, replaced the F.P.R and replaced the fuel pumb And still motor will not run. Any suggestions on the next positive move towards a running motor.

i can not believe all of you gear heads that pass on this issue. Reading other threads,it seams everyone has a opinon or answer. Now comes a real brain cramper, 45 views and not one reply.
Why do any of us bother to put stuff on this forum? To hopefully get some feed back from car guys and or girls who enjoy the sport of auto-mobiles. The issue of starts and stalls; Am i the only person that this issue has happened to? I think not.  

Have you checked to make sure you're getting fire to the distributor while the key is in the run position? As you know it take 3 things for a motor to run and if any are missing it won't . Hope I helped . Thomas  

My 98 ford expedition was doing something similar. There wasn't enough air in the engine at idle to keep it running. I changed the air aidle control vale. Before you do though try takinf it off and cleaning the inside with brake cleaner, wait for it to dry the put it on again.  

If you give it gas and it stays running then dies off, check for a vacuum leak.  

Make sure your Mass Air Sensor is working.

I've had a '90 5.0 for 10 years now and the IAC on it has never went bad on mine, But on my 2000 GT the IAC has done the same problem that you are explaining twice and both times I took the IAC off and cleaned it out with Berrymens B12 and then it works fine afterward.  

Make sure the engine block has a good ground to the chasis...      

good ground, proper voltage to coil & dist at start & key on ( I think current loss at on position is your prob) IAC clean & funtioning, like the other cat said if runs a wot then forget the coil & look for IAC & vaccum leaks (w/carb cleaner)  could also be a bum ign module- theyre cheap enough...good luck cant wait to see what fixed it  

I HAVE A 92 AND 86 MUSTANG 5.0 BOTH WERE DOING THE SAME THING THE START AND STALL PROBLEM I REPLACE EVERY SENSOR THERE IS WITH NO RESULTS THE LAST THING I DID WAS ADJUST THE TPS TO .98 WITH A VOLT METER AND THE PROBLEM WAS GONE