Heavy Rain Stall Out

[Brer]

1988 F150 302cc - New Plug Wires, Throttle Position Sensor, Map & O2 Sensor In heavy rain engine will start to miss and shut down - Doesn't happen in light rain or dry times. If you mash on the accelerator it will backfire and shut down, but if you ease off on the accelerator it will keep running as you slow down to about 20mph and then it may stall out. if it stalls you can wait about 7 minutes then it will start again and run for a few more miles when it may stall again. If you try to start in less time it just spins with no firing. Some small area must be getting wet, shorting out and then drying out in 7 minutes. Any suggestions as to what area I should look at? Thanks, Brer

[glc]

Replace the distributor cap and rotor.

[ymeski]

Originally Posted by glc

Replace the distributor cap and rotor.

If that doesn't work, your wires could be suspect if their older, also an older PIP sensor (Stator) An error code scan may divulge that, along w/ other possibilities, like an out of range MAP/or TPS. But start w/ the most likely. All of these potential causes require a certain dewpoint to be reached. Any heat reduces that to restore function, but at a reduced level, and it will eventually get worse till whatever component involved, fails completely. Sometimes observing the engine compartment in the dark wihile attempting a start will show something. You can sometimes duplicate the condition w/ a water spray must bottle, especially the plug wires or a cracked distributor cap.