My 7.3L Diesel is scared of the rain. If I drive in wet conditions - actually raining or just the highway having a lot of water on it, it cuts out. The engine doesn't die, it's like my foot slipped off the gas peddle. RPMs fall down to about 500 for about a second then takes off again. Once in a heavy downpour, it cut out long enough that I coasted to the side of the road, but most often it cuts out only for a second then picks right up again. Does it constantly until the conditions dry out. When I come onto a wet road from dry it takes about 6 minutes before it cuts out the first time.

ANY ideas? No one has ever heard of this before. Friend thought that the throttle positioning sensor was going bad, but that is inside the cab and cannot get wet (so I've been told).

Please help! I love my truck, but will have to trade in before winter if I can't get it fixed.

 

I'm going to guess that you have a ground issue- you will need to go over the electrical system with a fine tooth comb to make sure there are no shorts or chaffed wires anywhere. BTW, in case you don't know there are a TON of wires on these trucks!

 

Maybe try changing out the CPS and inspecting those wires. Thought someone recentlly had CPS issues in the rain.

And welcome to FTE!

 

I don't think it's the wiring. I've had it in to Ford twice and to a specialized-diesel shop twice. Both checked the computer and wiring extensively. on the last appt, the diesel shop resealed every electirical connection, but that didn't help. I will suggest the CPS - or maybe just change that out myself. What do you think about the Throttle Positioning sensor?

 

I don't think its the TPS myself. Just for grins and giggles, clean the battery terminals and posts up really well and see if it helps.

 

Welcome to FTE. Couple of questions for you. Have you ever had your windshield replaced? Have you ever had the CPS replaced? How long have you had the truck, and how long has this issue been going on? Lastly, how do you feel about driving around looking like a fool?

I asked the last question because we need to rule out all possibilities, including the windshield wipers being on causing the problem. There have been rare cases where driving with the wipers on has interfered with the CPS signal, which of course would not be noticed by a repair tech looking at the truck inside a shop.

Very small leaks in the windshield can also wreak havoc with electrical components. And instead of saying the diesel shop sealed every electrical connection (doubtful - there's just too many) can you find out specifically which ones they sealed / checked and let us know?

If the engine never coughs, sputters, bucks, jerks, etc. and only returns to idle, then the TPS is a possibility. Even if it doesn't get wet, the humidity level jumps up to 100% when it's raining, and perhaps it's the humidity causing the problem.

 

CPS was it for me . Same symptoms as yours, disappeared since I replaced with a DT466 CPS about 2 years now. Did Ford replace yours already during the recall ?

 

I changed out the CPS last Thursday. So far, I havent had any more problems with it cutting out. I've driven in two snow storms without problems, but it wasn't sloppy wet. Here's hoping the CPS was my fix. Thanks to all for your advise! Great websie! - Kathi

 

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