I went mudding two days ago, and when i got out of the puddles and got onto the road, i noticed the truck shaking badly. a minute or two later, the check engine soon light starting blinking on and off repeatedly. I left the truck in the driveway and drove the car yesterday. Today i got the truck back out and there was no more shaking. The light went off after awhile. I opened up my hook and there were mud splatters everywhere. This has happened before, when i sprayed out my engine compartment. When i took it in to get the oil changed, and mentioned it to the guy, he said it was water. Im assuming it the same thing again. Shouldnt these trucks be able to handle a little mud/water? The mud that i went through was more like puddles.....the deepest hole was maybe 6 inches deep....i just went a little fast through them. Is it just my truck or does this happen to others as well? It kinda sucks that i cant do any mudding without this happening. It only shuddered while i was taking off, didnt do it at any speed about 45.

2000 f150 s/c 4.6 automatic 4x4.

 

Do you have an aftermarket intake or factory airbox?

Exposed intake filters can get wet and suck water...

 

ah meant to say that. everything is stock.

 

You didn't get water in your engine, I get this all the time. Water splashed up and ran down into your plug wells down in the top of the engine, and where it's a dark hole there, water just stands, and this causes your plugs to foul out. The seals on the plug wells aren't always 100%, and sometimes, the water will evaporate and the plug will be fine again, but that's what causes your misfire after you go through any water, especially if it throws the water to the top of the engine, the only place it can drain is down into the plug wells. I change my # 3 and # 4 about once a month because of this. I'm going to have to come up with some kind of shield.

 

The exact same thing has happened to me, under the exact same circumstances. What is happening, is exactly like Pickup described. But the problem is if you get to much water under the spark plugs, it causes you to burn out your ignition coils. 4 in mine. Keep an eye on your truck and check to see if you can tell any difference in acceleration. If so, you might have an ignition coil burnt out.

 

If you are going to play in the water get out the dielectric grease. Every connector in my engine compartment has been coated. When was the last time you changed the spark plug boots? They need to be serviced as often as you would plug wires. Most everyone makes the same mistake of thinking that the boot will last forever. Yours are 4 years old. Time to change them. The OEM boots are designed to allow water that may seep down into the plug well to escape when it gets hot. As the boot ages it becomes brittle and can no longer seal and vent properly.

Regards

Jean Marc Chartier

 

Thanks for all the replies, glad to hear its not water in the engine. When i change the plugs, ill make sure and change the boots as well.