Wont start when it rains

[Caladd83]

Ive got a 1993 ranger 4.0 and it has trouble starting when it rains. Ive checked the coil and its good and ive replaced plugs and wires but still having the same issue. Ive sprayed water all over the truck and it starts up just fine not sure whats going on. Any info will help

 

[sgtsandman]

Does your engine have a distributor? If so, look for cracks in the distributor cap as a possible issue.

Try running the engine at night with the hood open and look for sparks. You might have to wet the engine bay to see anything and it needs to be pretty dark so light doesn’t wash out light from any sparking that might be happening.

 

[rusty ol ranger]

4.0L is EDIS.

So no distributor.

Your coil might function fine but might have a hairline crack or something in it. Wait till its dry and dump a cup of water on it, wait 5 min or so then try to crank it.

 

[sgtsandman]

Well, that answers the distributor question.

 

[Caladd83]

No it doesnt have a distributor i just tried soaking the whole engine bay in the dark and the truck fires right up and idled for about 10 minutes. I had the bed off a few months ago and soaked everything back there and still fires right up just only when it rains.

 

[sgtsandman]

These particular issues can make one pull their hair out finding the moisture intrusion.

I’m out of ideas at the moment. I’ll have to think on it.

 

[racsan]

I had that issue with my ‘88 2.3 , had just done a tuneup with all new parts. Ended up flat-towing it home from work. When it was in the barn I tried cranking it over, its not very well lit in there and I was able to see arcing all over the place. Bad.Brand new plug wires. put the old ones on and it fired right up. I quit going to “big A” after that, Im not even sure they exist any more.

 

[Caladd83]

Yea im stumped i put new plugs and wires on it hoping it would fix it but still acting up ill just have to keep digging. Once i figure it out ill post it on here thanks for the help.

 

[rusty ol ranger]

You dont have any cab rot issues do you?

 

[Caladd83]

Couple rusty places but no rot.... Im wondering if its sucking in moisture somewhere

 

[Caladd83]

Because i can soak it with a water hose and it will start just fine but with the rain and moisture in the air it gives me trouble

 

[DILLARD000]

This thread reads like lyrics for
The Perfect Country & Western Song

 

[Caladd83]

Haha damn

 

[Curious Hound]

This thread reads like lyrics for
The Perfect Country & Western Song

We could write a new one.

My truck won’t start
And my dog won’t howl.
If my girlfriend leaves
I’ll just throw in the towel.

 

[RonD]

Clean MAF sensor

MAF sensor is there to WEIGH the air, higher humidity can cause it to mis-read the weight

Also do 50/50 test when there is a wet day/no start
Spray fuel into the intake and crank engine
If it starts up then its a fuel delivery issue
If it doesn't start up then its a spark issue
50/50 instant results

Also is the rainy day no start JUST on first startup of the day, does it start fine the rest of the day?


Also because of the age you may need to pull out the computer and inspect the circuit board
There are 3 capacitors on the board that can leak and cause odd issues
Only cost $5 to repair, I just did my 1994 computer
Different symptoms, but there are no specific symptoms

Also higher humidity can cause "shorts" in a dirty circuit board, so might be worth a look, its free, lol