1986 Ranger, 4 cyl, auto, 46k miles. Runs fine when it is cool, but when it is hot outside it misses (acts like it's not getting fuel) and then will quit running. After it sits for a while it will start and run fine again. Have replaced the plugs, wires, fuel pump and ICM. Could this be vapor lock?
Did you replace the fuel filter? And is the vehicle one of the carbureted or fuel-injected ones? If so you could have a carburetor issue. It sounds as though something is going amiss when it is heated up. You replaced the ICM, are you referring to the coil, or the actual engine module? How about the distributor cap and rotor button? You may also have an issue with one of the sensors. 1986 Ford Vehicles used an EEC-IV system which was pre-OBD-II. You will need a code scanner that can scan Ford EEC-IV vehicles to pull engine-related codes on this vehicle.
I had a similar problem, check your vacum booster pump. If there is a hissing while you are driving, that gets louder when you stop, odds are it a vacum booster pump.
if it is carburated make sure the heat riser is closing when it gets hot. they seize up a lot on old shitty fords. lol. or the oxygen sensor is bad, the oxygen sensor only affects the engines control systems once its warmed up. and make sure the ECT sensor is working (Engine Coolant Temperature) and connected
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