Instructions for EEC-IV self-tests (aka "pulling codes") www.dalidesign.com/hbook/eectest.html

 

I dont know if this will fix your problem,but the main neg battery cable{BIG ONE} needs to be grounded to the Engine.The motor mounts have rubber in them and do not conduct elec. real good,also check and make sure that your ground strap from the back of the engine to the firewall is good.JMO

 

Strange as it may be, this does sound very similar to the way my bad fuel pump acted. Ran fine cold, wouldn't run worth crap when warm. New fuel pump, and the problem hasn't been back in the past 50k miles.

 

Raidy.What did you find? I would like to know.

 

I had the same problem and it was the pressure regulator . Replaced with a 45psi unit and it solved the problem

 

I am voting fuel pressure loss. Also, might check the MAP sensor since it detects engine load from vacuum. Check the rest of the vacuum lines while your at it.

 

I have the same prob as Raidy. Took 15 hours to make a 6 1/2 hr drive in the heat, stopping at 10-45 minute intervals for the car to sit long enough to run again. The engine is not overheating, new in-tank fuel pump. High pressure fuel pump tested good, and battery wiring seems good. A friend told me this was a common prob with early Bronco's. The early computer board thinks the engine is hot and shuts off the fuel, and that is exactly what it feels like. It feels like you're running out of gas. What and where would that computer board be? Any suggestions?

 

I think what your friend is referring to as the computer board is the ECU, which is located behind the passenger side kick panel in the cab. But ECU problems are rare, it's usually a sensor or actuator that causes the problem. The first thing to do is check for fault codes, which can be done with a code reader (about 30 bucks or so) or by more primitive methods as detailed here:

Ford Fuel Injection How To Run a Self-Test

But also, be sure to check everything already mentioned in this thread. Specifically, I'd tend to suspect your ignition module.

 

i have a 86 bronco 2 with a 2.9 engine, I rebuild the engine and everything was find for about 200 miles, then it started missing and running real rich. i replaced the egr valve the fuel pressure regulator, the high pressure fuel pump, new plugs and it still running rich. Help

 

How old is the O2 sensor? This controls the A/F ratio. Also check for any leaks in the intake system. How old are the fuel injectors, they could be sticking open. Leaks in the exhaust system before the O2 can also cause a problem.