I should have known better. It’s been quite a while since I’ve paid any attention to cleaning up my engine bay, but since I’m trading the truck in on an ’05 in a couple of weeks, I thought I’d do what I’ve done many times before – clean it up. So, I grab a can of Engine Cleaner from the local Auto Parts store and follow the directions – except for the part about covering everything electronic with plastic. (I’ve never done that before.) I made sure not to aim directly at anything electronic and when I flushed everything with water I used a very gentle spray (no pressure wash).

Well, you guessed it. The truck ran fine right after the cleaning, but later in the day it stated mis-firing and bucking. After a 20-mile trip to my brother’s house, it kicked on the Service Engine Soon light. The symptoms are an occasional loss of power that definitely feels like a mis-fire, and some occasional bucking at 40 – 60 MPH going up hills. I’m not sure if these are different symptoms / problems or not. I checked under the hood for any obvious collections of water on things electronic and made sure all of the connections on the coil packs were still tight, but it didn’t seem to have any effect.

This morning when I went to work (about 4 miles), there was no Service Engine light and it seemed to have full power – or at least as much power as a 4.6 usually has. I didn’t get up to expressway speed and I don’t think I detected any bucking. Could I have gotten lucky? (Not with my luck.)

Here’s my questions:

1. Am I an idiot? (OK, don’t answer that)
2. Since the Service Engine light is out, should I assume that whatever it was is now dried out and all better now?
3. Should I go to the Auto Parts store and have them plug a Code Reader in?
4. Should I do some spark plug diving to see if I got water down in there? If so, (since I’ve never played with Coil Packs), how does one do that?
5. If I’ve damaged a Coil Pack, will this problem return the next time it rains or snows – which should be later today?

Any help you guys could provide will be greatly appreciated. Man, this is the last time I clean my engine! Thanks.

 

I'd unhook the battery ground cable and turn on the headlight switch for a few minutes, this will clear the pcm of the codes that were set when the CEL came on.

This will give the pcm a clear memory of any codes for the new buyer.

Gene

 

I've had this happen several times. just pull off your plug boots and blow around them with an air compressor to get rid of any water that has settled there. Also be sure to put some new plug boot grease on.

 

OK, sounds like two good suggestions. I'm thinking I'll do some "de-moisturizing" before I go clearing codes. Now, since I've never messed with the Coil Packs and / or plugs before, how do I go about doing that - so as not to cause any more damage. (You've seen how my luck is running so far.) Thanks!

 

JMC,

Give me a little of your patented help here. Thanks!

 

Get the codes red to see why the SES light was on. This will tell you if it was a misfire or not. If it was a misfire the chances are that it was indeed caused by the moisture/water. If it is a P03XX code then it will tell you which cylinder was involved and you can spend a bit of time fixing it. FYI. All the connectors in my engine compartment have dielectric grease in them. If it is something else then you will not have erased the codes that will tell you what it is. We don't want you showing up at the dealer to trade it in with a SES light.

Regards

Jean Marc Chartier

 

Don't reboot the computer unless it really has to be done.
Reason is the computer loses all the 'learned' engine control and will be some time until it regains the programming back.
In the mean time, expect the engine not to run the same until learning has occurred.
This is even reffered to in the owner's manuel.

 

JMC,

Thanks buddy. Even though it seems to be running fine and the SES light is out, I stopped at Advance Auto Parts and they slapped a code reader on it. They pulled (and cleared) a P0303 code which is apparently a Cylinder #3 misfire. My plan is to run it for a few days and then have them re-read it. If there's no codes, I'm just going to wait about a week for my '05 to arrive. If it pops another code, I'll work on that cylinder only. By the way, exactly what should I do with the dielecric grease? Just the connector? Thanks!

 

Becasue I go off road with my truck I coated the contacts of every connector with Dielectric grease. Pull them apart grease on contacts click them shut. I mean every one. The PCM, the bulkhead connectors, the tranny connectors, every single one. It is a bit **** but it keeps the water out. I also have grease on the plug boots where they meet and cover the plug. In your case pull the #3 injector connector and coat it. Do the same for the coil connector. You should be fine after that. Clear the codes then don't clean the engine on thet truck any more.

JMC

 

You ARE lucky, if my truck misses, you can bet that the plug won't fire again unless I get it out of the truck. I've never put a used one back in, though, so they may still work, but if mine misses once, it never fires again until it has a new one in it. This was a problem for me for years, so no, you're not an idiot, it happens to all of us, it's just the way the plugs go straight down into the wells and it holds moisture.

 

The first time I test drove my truck a few months ago, it ran a little rough. The salesman later told me that the detail crew got the plugs wet and he had the service department put new plugs in it. I'm just glad that the dealership did it before I bought the truck.

My advice- let the dealership detail the motor (and fix anything they screw up by getting it wet). Your trade in value won't change based on how much dust is on the motor.

 

Had the same problem about 2 years ago now on my 2000 and it was water in one of the coil packs.

 

Thanks to everyone for the advice. All appears to be well now and I leaned my lesson. It amazes me that something that gets as wet as the engine bay could be so intolerant to a bit more water. Oh well, I'll stick to being **** about the outside of my truck from now on. Thanks again!

 

I just wanted to add a quick note here. I have washed my engine compartment once so far, with no problems, BUT, I was already aware of the COP boot problems. The method I used (after a little helpful research here) was to spray down the underhood area with Simple Green, let sit a few minutes, then rinse with my electric pressure washer. I guess my nozzle is just right, maybe 15* fan pattern? But if I held it about three or four feet away, it really just misted to rinse, plus, I kept the stream moving at all times. The final step, and likely most important, was to grab my Shop-Vac with the detachable leaf blower, and blow dry everything. Then wipe down hoses, plastic bits with Armor-All wipes, squirt linkages, cable ends with some PB Blaster.

Easy.
Looks Great.
No problems.