engine cant handle water

[2stroke]

My engine is from a 94 explorer, and one thing I've noticed is that it doesn't like water puddles at all. If its raining hard, it runs fine. Even if I wash the underside of the truck, it runs fine. The first time I noticed, I hit a bigger puddle faster than I should have, and the engine started cutting out. I figured the spark plugs got a little wet, and the engine cleared up in about 10 minutes. Today I drove nice and slow through a puddle that couldn't have been more than a foot deep, and there was almost no splash, and again, the engine did not like it at all. Its always off road, in muddy puddles. I've never had a problem on the road at all. I'm just wondering if anyone has ever had this happen to them before. My last truck, also a 94, never had a problem. You can dunk that thing up to the air intake, and it will run. The only sensor that I know of that hangs anywhere near the bottom is the crank position sensor, but I don't see how that could cause this big of a problem by just being splashed.

 

[Number4]

Something electrical must be getting wet. Water splashes pretty good distances. I'd unplug as many connectors as you can find and fill them with dialectric grease.

 

[Anime]

I would guess that you have cracked/damaged boots for the spark plug leads/wires if you're getting something external wet from the tires and it's affecting the engine immediately, either that or the battery negative/ground wire on the right side that goes to the frame, although neither of those seems likely given how little water gets even close to the engine or plug wires, and how much the ground cable gets soaked when driving in the wet.

More likely is that there's a crack or hole on the inner fender that is letting water get in somewhere like the fuse box or some wiring or connector.


My suggestion would be to grab a hose and spray upwards on the inner fender with the hood open, you might see where the water is getting in. There are one or two holes from the factory that go through already, but they shouldn't be near anything, so you may want to tape or plug those so you only see the leaks that matter.

 

[2stroke]

Its not the plugs. The first time it happened I pulled the boots and greased them good, and there was no sign of water. The wires are fairly new too. I never thought of water hitting the fuse box. I suppose the tires can kick water a good distance even when slow. Maybe the difference is when off road I have my wheels turned where on road I can hit puddles straight on? I'll see about spraying water up when its running with the hose.

 

[Anime]

I've driven deep in soupy, muddy water, and turned the wheels from lock to lock over and over in four wheel drive, spinning tires going forwards and in reverse, and the MOST that ever got on the engine/exhaust manifolds was some mud splatter. The inner fenders (and the body) were COATED in mud. The rear part of the front bumper, the outer front fenders, the doors, the windows, the entire rocker, the outer part of the frame, and the underbody between the frame and the rocker were coated with the stuff, but there was just a few splattered dots of mud on the exhaust manifolds and the various metal ABS lines and wire looms.

Even with that big, gaping space, those inner fenders seem nearly perfectly shaped to do their job.

Unless you have tiny 225/70R15 tires, I doubt much of anything is getting onto the engine itself or the wires through that gap, unless there's a crack somewhere.

That's why I'm guessing if it's related to water, it's getting in from a hole in the inner fender and making contact with a wire, connector, something.


Another way to check is using the spray bottle trick - fill a spray bottle with water, and put it on the fine mist setting, then start the engine and spray the bottle onto the plug wires/wiring - I'd say do it from the outside through the inner fender hole - and see what happens. When you get the same result you describe, you've found the location for the issue.