My 2002 Ford Escape XLT (120k miles) chugs and sputters when started in wet and/or humid weather, and the check engine light flashes (sometimes goes solid and stays on for days later). In my non-mechanically inclined imagination, I would say that the sound and effect are as if there are air bubbles in the fuel line causing the engine to sputter when I step on the gas, however the problem continues even when I'm not accelerating. Also, the car shakes and trembles terribly when this is happening. This issue comes up when we've had rainstorms for a day or more, or when heavy humidity and fog roll in. Generally the engine begins to run more smoothly after a 30 - 90 minute drive, and the check engine light will go off a day or two later. I have changed the fuel filter, use premium gas, and have replaced the ACV valve once when the Ford dealer diagnosed an instance of the check engine light. I would be so grateful for any ideas - this issue is driving me nuts!
I'm having the same problem with my wife's 2003 Escape with the 3.0 liter engine. Codes P0316 (misfire within the first 1000rpm's) and P0304 (misfire cylinder #4).
I have replaced the plug twice, replaced the ignition coil, wiggled the wires at the PCM with no luck. The codes will clear once the engine is warmed up and then there is no misfire present the rest of the day.
As you state above, this problem only occurs after the vehicle has not been run for sometime and it has been raining.
any results my Daughters 01 with 150,000 has started to do this only in humid or real rainy days check engine light blinks then goes soild and the code is misfire in cyl.3.then it clears up runs like a champ and light goes off!
I'm betting on it being a cracked coil (small crack in top of one of the plug coils). Same thing happened to me with my 2001 Tribute, would run fine when dry weather, barely run and stall during damp, humid weather or early mornings. Found one of my coils had a crack across the top, replaced and runs like a champ ever since.
Take it to one of your local auto stores that will check the trouble code that your computer is storing. The auto stores around me do it for free (AutoZone, O'Reilly's). Once you find out the trouble code, if you don't have a repair manual, just post it here someone will look it up for you. Some codes basically tell you exactly what the problem is, some give you a good idea. I think everyone is on the right track it's some kind of ignition problem, like a bad coil. If so the #4,5,6 coils are super easy to replace. the #1,2,3 are a pain because you have to take off the intake manifold. Just depends how mechanically inclined you are. First see if you can get the trouble code, and go from there.
Also......STOP using premium gas!!!!! Waste of money. Higher octane gas just means it's harder to ignite, which helps higher compression higher horsepower engines get their full horsepower, by not preigniting or detonating at the wrong time. It's not good to use that type of gas in an engine made for 87 octane....This will save you 30-50 cents a gallon.
the code that was showing was p0303 which is misfire in cyl.3. Bought 1 coil pack and put it in also found the vacuum line that goes to egr valve where it connects to manifold was bad so fixed that.And the vacuum line that connects to the manifold by the throttle body that runs to the thing by the master cylinder looked really bad so replaced it, along with new lower and upper intake gaskets.So we will see if its fixed in the morning.
I know this is a couple years old but did you ever get the problem back or did it seem like this fixed it? I'm having the same problem and what I did to narrow it down to what the problem was is that I took the coil pack from the cylinder in question (cylinder 2) and switched it with one in the front like cylinder 6). I figured if the light comes back and its the cylinder 6 then the coil pack is bad. If its the original cylinder then it must the spark plug. If its the plugs then I'll change them to a better spark plug. If its the Coil pack then easy change out. we'll see, I did it today and it seemed to run great may be it needed a cleaning. I clean each plug ( they didn't need much if any) rechecked their gap, put electrical grease on each spark plug along with anti-seize. The true test will be how well it runs in the next week or two. someone said earlier it seems to chug in colder/damp condition I would tend to agree in my situation at least. Its better during the mid-day sun is at its most versus early morning or at night. I'll Keep you guys posted.
Just went through this with my 2001 XLT 189,000 miles. The first time in the rain, the check engine light would flash ,no codes stored, returned to normal when weather dried up. A week later it did same thing, drove it until light came on solid. Code was P0305 misfire cyl. 5. Replaced coil pack as I had changed plugs and intake gaskets 6000 miles ago. This morning it was cool and foggy and car had sat out all night in damp/rain. Started and ran without any hicups. After 3 or 4 cold starts and drives the light cleared and all seems well. Will update on the repair in a few days.
I have a 2003 with the same problem twice- first at 60,000 miles while driving cross country. (Sputtering, misfire, rough idling especially on high humidity days)Had to have the car towed to a dealership from the side of the interstate when it died and wouldn't restart. I was stuck in Memphis while the dealership pulled the engine to replace all six coils. This does not need to be done - yes some of the coils are hard to access but do not let a mechanic tell you he needs to pull the engine to do this!
Second time at 120,000 miles had the same issues you're describing, but better mechanic at home. They replaced all 6 coils and all my spark plugs for less than half the cost of the dealership, problem solved.
Two months later though, the alternator went out. A week later that alternator went out, frying the batttery which had to be replaced. Now I'm replacing wiring and my emergency brake lines, which locked down.
it seems common that replacement alt. are a hit or miss A few others here on the site had the same issue of replaceing the alt. and it fails.Many advice that for replacement go and buy a new one from Ford.Thats crazy if they pulled your engine to replace your coil packs.You do need to pull the intake manifold which is a pain but not that bad of a job.To do a plug change it took my adout 3 hours but I cleaned every thing.