Hi everybody- I'm new to the forum and somewhat new to Fords in general- especially newer Fords, and I need your help.
I'm a driver/courier for a large and impersonal corporation, and the company vehicle I drive is a 2002 Ford E-150 van w/ (if I recall correctly) a 4.6 L. V-6.
It's got 181,000 miles. Over the past year, I've replaced the plugs, wires, EGR, and oxygen sensor, and it was running like new...until Saturday.

That's when I took it through one of those automatic car-washes. And as soon as I drove over the undercarriage sprayer, the van started spitting and sputtering, the engine light came on (often blinks as well), and the thing has just been running like crap ever since- especially from red light starts, even backfiring on occasion..
The guys at Autozone checked the computer codes and it came back w/ Cyl. 1 misfire, and Misfire @ 1000 rpm. However, I don't really think this helps me much. The last time it had a similar problem (and the computer read similar codes), is when I replaced all those components listed above- w/o solving the problem....I eventually found a disconnected vacuum hose- problem fixed. *neither myself or my boss were happy abt that* So this new problem really irks me, as I'm an old fashioned guy- give me an engine w/ a carburator, a distributor, and vacuum lines- forget that computerized stuff- and I'll fix it no problem.
The only other thing I can tell you is that on prior occasions, after it rained, the van would act similarly, but the problem would go away after a few hours. This time it's been three days and there's been no improvement.
Now I've read a number of other posts on this site, and it seems others have had similar problems- but mainly w/ COP systems. Obviously, since I mentioned plug wires earlier, this engine isn't COP. Any other ideas as to what might have gotten wet or what needs to be replaced?? Thanks.

 

Could be the throttle position sensor. Might be a decent place to start after everything you already replaced. Could be the spark box too, but that would be more money. Interestingly as well, our 96 minivan (not ford, but still would have similar issues) read out a misfire on cylinder 6, and the fuel pump was bad. Generally though, fuel pumps tend to go bad after they've heated up. Might want to bring it to a garage where they can test fuel pressure and that sort of thing and tell you for sure what is wrong rather than chasing the same problem with a bunch of parts. A manual will tell you how to check the tps.

 

Welcome to the forum

Sounds like water got down in the spark plug pocket and is shorting out the plug wire. Did you put dielectric grease on the plug wire boots before putting them on the plugs? This helps seal out moisture and eliminates misfires. Also, what brand plugs and wires did you use? Only Motorcraft or Autolite double platium plugs seem to run right in these engines. Motorcraft wires are better than most aftermarket brands too.
I would start by removing the plug wires from the plugs, take compressed air and blow out all of the plug pockets, put the dielectric grease on the wires and reinstall them and see if the problem goes away.

 

I was just going to say the same thing LxMan1. Please, do what he just recommended.

By the way:

4.6L = V8
4.2L = V6

 

So, if it's got wires, sounds like a 4.2 V-6. It does help if we identify the engine right off the bat. Locations for the various electronics are gonna be different.

-Kerry

 

You're right, it's a 4.2. My bad. So I've rechecked all the plugs and wires and boots- all were nice and dry- but went ahead and applied dielectric grease to prevent future problems.
It is obvious that cylinder 1 is the problem though. All the plugs were nice and greyish except plug 1 had obvious carbon buildup at the base near the threads (dry fouling?) though the electrodes looked ok. I even went so far as to take the coil pack off so I could examine/clean out the sockets, but the problem's still there...I guess that doesn't necessarily mean the coil pack's not bad...

 

Take the spark plug from cylinder 1 and switch it with another cylinder. If the code changes to the new cylinder, then it is obviously the spark plug.

 

Sounds to me like the crankshaft position sensor got wet, it is located lower eng timing cover. I'll post a pic look for 6C315 dry out the connector. It is kind of a common thing!


Ed

 

Ed, you got the pic for the 4.2? I know the crank sensor should be in close proximity to the crank, but may be on the other side for the V-6.

-Kerry

 

Does thing engine use a distributor? if it does, open it and clean inside with an electronics cleaning spray, or use some sprayed lube (marine formula worked for me allright).

 

It's not the best picture, but this is what we have!

Ed

 

First of all, thanks for all the help on this- you all have been very enlightening. Before this, I had never heard of dielectric grease, nor was I aware of the crankshaft position sensor.
So I did find the sensor. On initial inspection, I thought it might be the problem, as the rubber housing had cracked, exposing the wires inside, but the wires' individual insulation were still intact (and dry). Still, I cleaned all of it- wires, connector, and sensor, then thoroughly wrapped the rubber housing w/ electrical tape (and zip-tied the ends of the tape), and, just for good measure, applied a little dielectric grease to the lip of the connector before plugging the sensor back into it, and wrapping the connector in electrical tape as well.
Additionally, I did change out that plug and wire for cyl. 1- just to see what would happen.

Problem's still there.

However, as I've had to live w/ this problem for a while now, I have noticed a couple more (possibly) helpful...symptoms:I'm reminded of jb1390's theory abt. the overheating fuel pump...but why would that only effect one cylinder, and why (unless it was just bad timing) would that start w/ the car-wash?

So, any more advice? Or is it time I just eat 80 bucks and get a diagnostic?

 

It is peculiar that it effects only one cylinder... but that was why so many were leading towards the spark plugs/wires. Keep swapping plugs until you've exhuasted that route or a CEL comes on. While the #1 plug may have given the intial code, there may be others since you swapped plugs - in some cases the CEL never is on, but the truck will store a code until it becomes chronic before actually turning the CEL on (CEL-Check engine light).

When you wash a car, especially at an automatic car wash with spray jets coming from underneath or from a low sideways angle, the drivetrain electrical components have the potential to get water in them. Things inside short together. The sensors either dryout and everything is fine or, as in your case, trouble continues. Another good item to check is any hoses, specifically any carrying a vacuum.

The problem is engine speed related. The problem may be the crank sensor still. The sensor may have gone bad. It works fine at low rpms, but when your engine speed gets going, the sensor has issues. Another item to look at is the injectors or fuel rail.

In your case, you know that when you rev the van up, it runs like poo. It may be worth the money at that point to take it to the mech and have them pull engine specs before, during, and after that same engine rev.

-Kerry

 

A basic diagnostics check and fuel pressure check when the truck is acting up shouldn't be very expensive-a local garage can tell you exactly how much if you tell them what you want-maybe fuel pressure, oil pressure, and electronic diagnostics while driving it. Shouldn't take long and they can tell you exactly what to replace before chasing sensors and stuff. One other thing to check-look for any ground wires attached to the engine-especially any that can get wet. Take them off and wire brush the connections, and see if that helps. The engine-and connections will change as the engine heats up due to expanding components. It doesn't cost anything to do either.

 

Update: Despite my best efforts the problem continued to get worse until it got so bad that the van wouldn't even get over 30 mph. The boss had no choice but to actually take it to his mechanic- who ran a diagnostic and then proceeded to check everything I (and you all advised) already checked. Even he, the certified mechanic, couldn't find the problem- and actually gave up after ten days. We're taking it to the dealer tomorrow...