I have a question for all the EFI experts here on FEP. This is actually my 1986 Bronco with a 5.0 SEFI engine, AOD transmission. All stock and everything is in working order minus the air pump. The vehicle runs very well and generally has no issues. Starts up within a second or two every morning. Runs great with no issues. The problem is that if I drive it and then shut it off, come back to restart after @ 10-15 minutes. The vehicle will crank and turn over, but generally will not start until I do that at least 3 times and or I pump the accelerator a few times. I thought it might be a fuel issue, but honestly not 100% anymore.
I have done a full tune up with new cap, rotor, wires, plugs, oil change and filter. I just replaced the fuel pressure regulator with a new one, but no change. Lift pump in the tank is new, but frame rail Hi-pressure is old/original. I cleaned the throttle body, IAC, and throttle body passages of any and all carbon build up. Still have the same problem.
The vehicle will restart virtually immediately if you shut it off, but let it sit for @ 10 minutes or more and it is hard to restart. Let it sit overnight and it will fire right up. Any ideas, thoughts would be appreciated. I have run out of ideas and don't really want to throw parts at it anymore. I do have a new IAC coming for it, but that will be this weekend before it's installed.
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