my dad has a 99 f250 with a 7.3 diesel motor. The pickup runs good but when its driven in rainy conditions the motor will cut out or completely die, it runs fine in dry conditions. Anybody got any ideas what might be wrong

 

Windshiels wipers tend to cause a problem with the CPS. Check all the connections going to the wipers and check the ground connections as well. I had the same problem, I cleaned all the connections and replaced the CPS and the problems went away. Others have done the same. hope this helps. and welcome to FTE

 

i believe the cps/ connection can also get water in it and cause this sort of issue. disconnect, take cps out let every thing dry and then put some dielectric grease or vaseline on it to keep moisture out.

 

I think this is the problem. Use high temperature grease around the area of the O ring of the cps to seal out the water.

 

Ditto on what BOB said.

 

My CPS failed in the rain. At 70. On a 4 lane in each direction freeway. "Luckily" it bucked it's way to an offramp and quickly a parking lot where I swapped in my spare.

 

Also Some aftermarket cps's have an issue with the windshield wipers going. Not even a water issue. My SMP CPS has that issue.

 

thanks for the help I'll give it a try and see if it helps

 

cps mine did the same thing

 

another question by cps do you mean cam position sensor

 

that is correct