302 stalls when warm
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Freshman User
Joined: May 2004
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302 stalls when warm
I have been trying to find the problem and sure could use some help. I have a1992 F-150 with 302, e40d., 100,000 miles. This truck runs great when cold. After it warms up it will stall. This takes about 7 miles. The engine will get home if you unplug the MAP sensor. Parts replaced include the computer, fuel filter, ignition module, coil, ignition cap, rotor, temp sensor, Map sensor, fuel pressure regulator, egr position sensor, plugs, the sensor inside the distributor. Some of these have actually been replaced two times lately. The truck smokes badly when warmed up. Smokes a little when cold. I think it is oil smoke. Dark but not really black. I have had to replace the plugs 3 times because they get gasoline soaked. I have checked the fuel pressure on both tanks and read from 30 to 40 psi. I have tried several times to read the codes, but nothing definitive yet. The engine trouble light does not come on unless you unplug something. No light while driving. If anyone has any ideas, I would like to hear them.
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Joined: Jul 2004
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I would suspect that the smoke is from unburned gas. It sounds as though the truck is getting to much fuel. When cold, it needs more fuel so it runs ok, but when hot it chokes on fuel. I have 4 guesses 1 of which you have already done. In the order of most likely.
The coolent temp sensor is the most logical, but you have already replaced it.
O2 sensor. If not the coolent sensor then I would suspect this. Sending a lean condition to the computer, thus the computer increases the fuel.
The air box temp sensor
Dirty fuel injectors. Maybe they are so bad that the injectors are not closing all the way and dripping fuel.
It is also probable that some damage has been done to the cat after all this unburned fuel running through it. Although I don't think this is causing your current problem, it will probably become one. I would not recommend running the motor with the exhaust disconnected for testing now. With a rich condition like yours, there will surely be flames shooting out the manifold.
Hope this helps
The coolent temp sensor is the most logical, but you have already replaced it.
O2 sensor. If not the coolent sensor then I would suspect this. Sending a lean condition to the computer, thus the computer increases the fuel.
The air box temp sensor
Dirty fuel injectors. Maybe they are so bad that the injectors are not closing all the way and dripping fuel.
It is also probable that some damage has been done to the cat after all this unburned fuel running through it. Although I don't think this is causing your current problem, it will probably become one. I would not recommend running the motor with the exhaust disconnected for testing now. With a rich condition like yours, there will surely be flames shooting out the manifold.
Hope this helps
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Freshman User
Joined: May 2004
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Well, the symptoms only show themselves after the engine is warm, so I do not think it is dirty injectors or a damaged catalytic converter. I think some sensor may be sending a wrong signal when warm or some other component is failing when warm. Thanks for the input and if anyone else can think of anything, please do.
