I just bought this truck 2 weeks ago - it has 143km on it and the only thing I have done is added a K&N air filter. I washed the vehicle tonight and sprayed the outer sides of the valve covers - not the entire engine. The engine is not running smooth anymore since I washed it. Now it is bucking a bit at low RPM and also lags a bit when you hit the gas from the line and sitting in park. When the RPMs get past the lagging stage the PRMs don't go up smoothly as it accelerates. It hesitates and then speeds up again normally. Any ideas what my problem is? I'm hoping that wherever the water got (if that's the case) that it will evaporate over night. As well, can someone tell me what a MAF sensor is and where it is located. Also, what do I do to clean it. Thanks.

 

Sounds like you got water under one of the coil packs. If that is the case the water will not evaporate overnight. The best idea is to start the motor, and begin unplugging coils one at a time. Find the one that doesnt not make a difference and that is the one with water in it. Pull the coil pack out and dry out the plug bore and coil. Re-install coil and all will be well. I go through this regularly because I take my truck offroad frequently, and wash the motor after every trip. No big deal, just a little time consuming...good luck.

 

it is usually the passenger side rear that gets wet to pull that one out first and check for water... after u dry them out put some dialectric grease inside to keep water from causing u same problem again.

 

I'm not sure if water was my problem or not. The engine has started acting up again. At times it seems like it's bucking a little bit - very minor, almost not even noticable but you can tell that something isn't right. It only seems to do it after it has warmed up. Engine idles at 500 rpm which I think is low - is it? I cleaned the maf sensor and this didn't help. Any ideas?

 

Yes 500 rpm idle is low. Should be 750 in P, 650 in D. The IAC controls idle so do a search. There is a lot of info on cleaning it. My truck ran fine cold but would not idle when hot so I opted to replace it at 94000 mi cause they do wear out. $110 from Ford and 1 hour to install myself. Good Luck.

 

As was already said, you have water in the spark plug holes. You need to remove all the coil pack and get the water out of the holes. You're going to need a source of air to blow all the water out. Very rarely does it just dry out on its own.

 

I really question whether or not it is water in spark plug holes. If it was water in the spark plug holes wouldn't it do it all the time?? The truck runs fine in the morning for the first 15 minutes or so (-7degrees celsius to 7 degrees celsius is outside temp), but when the truck warms up it starts acting up. A previous posting that I read mentioned about a bad coil pack - symptoms were similar to a "fish tugging on the end of a line." The same posting that I read mentioned the oxygen sensors. Apparantley the computer ignores the oxygen sensors until the engine warms up. Although the idle appears to be low at 500rpm, it is always at 500 regardless of temperature and never fluctuates up or down besides when first starting it - revs up to 1200 or so and then idles down.

 

Has it tripped your Check Engine Light (CEL) yet? If not, it probably will shortly. When it does, get the code(s) read and you'll see fairly clearly where your problem is. You've probably joined the "I don't wash my Ford truck engine anymore" club. (Closely related to the "No good deed goes unpunished" club.) I joined that club just last year when I gently washed the engine on my 2002 - just before trading it in. The problem? Water down a plug hole.

 

2stroked - how long did the water stay down in the hole? I find it hard to believe that the water won't evaporate 3 weeks later. I guess I should pull all of the coils and have a look. Do I need to pull my fuel lines to get the coil packs off? Is there a rubber boot connected to the coil pack or is it separate? My CEL has not come on yet.

 

My wonderful experience lasted about a week and pretty much cured itself. I had Advance Auto Parts read and clear the code - which was a misfire on one cylinder. If you do a search, I think you'll find a ton of useful information on this very situation. The early ('97 & '98) trucks were much more prone to this than later models. You won't believe how much water can hide down there. Then if you foul a plug, you get into a whole different joy when you have to replace the plugs. (Hint: Do a search and be careful!) My savior on my whole experience was JMC. He helped me through the entire mess. You might want to look him up. Now I have an "05 and the motor never gets hosed!

 

If your truck has COP's, you probably have one that is going bad. My 4.6 did the same exact thing. It was really only noticeable about 45mph after the tranny shifted to OD. If you've concluded that you don't have water in the plug holes, then go out and buy one COP (about $50) and swap them out one-by-one until the bad one is located. My CEL never came on in this situation. You will only need to remove the fuel rail to get to the #7 COP on the drivers side. It is blocked slightly by the fuel pressure regulator. Very easy to do. 2 screws hold the fule rail in place.

Good luck

Anthony

 

I just took the truck to a service repair shop and they hooked it up to two different machines and unfortunately the machines showed nothing. The guy working the equipment did say that he thought something could be wrong with the units themselves as they were "locked out" - whatever that means. Looks like I'm down to pulling the coil packs to see if there is any water down the hole. The guy I talked to claimed that the reason it doesn't do it in the morning is because the water is sitting down in the hole but as the engine warms up the water evaporates up into the boot and then starts to cause the arcing. Then when the truck sits over night the water condenses and falls back down into the hole - the reason why the truck doesn't do it when it's cold in the morning (or has been sitting for 10 hours.) Does this make sense to anyone?

 

Sure that makes sense. I had accidentally spilled some coolant over one of my COP's and 1 day later it failed. Started running really bad, followed by a CEL. I can't say for sure the coolant ruined the COP, but the timing sure is coincidental.

But you are in a pickle, you don't know which hole might have the H2O!?
I hope for your frustrations you get a CEL which may ID your problem.

 

This makes complete sense. The water never has a chance to evaporate. Try removing each COP (if your truck has them or each plug wire) and take a paper towel and stuff it down into the recessed area. Remove the paper towel and check if it's wet. Best time to do it is when the engine is cold. Do this for each cylinder beginning with the #4 then 3, 2, 1, 5, and 6. These are the easiest to get to. 7 and 8 require the removal of the fuel rail. Not tough to do. 2 screws hold it in place.

If this does not fix your problem, you probably have a bad COP. As I suggested earlier, go buy 1 COP from Autozone (about $50) and swap it out with each one, one at a time while taking it for a drive in between. I would almost bet that it will fix your issue.

Anthony

 

Thanks anthony. I will do it on saturday morning, allowing the truck to sit overnight and condense any water that may be in the boots. I'll let everyone know how I make out.