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Ford Escape Engine Misfire

I'm hoping someone can help- about at my wits end with this one. I've been having problems with my 2001 V6 Escape having cylinder misfires for about a year with no luck finding the cause. The car stumbles and pops on startup, usually on acceleration, and sometimes when cruising. I've had P0300 through P0306 codes - changes all the time and without any discernible reason (i.e. doesn't change when I move the ignition coils). Right now it says cylinder misfire on 1,3, and 5. It also smells like gas - I believe it is running too rich. I've replaced just about every part and sensor I can think of: ignition coils, plugs, IAC, MAF, PCV valve, EGR (sensor, valve, and solenoid), coolant temp sensor, air filter, fuel filter, fuel pump, fuel injectors, 02 sensors, camshaft sensor, crankshaft sensor, and probably more that I can't remember. I've done a vacuum test and gotten good results, and a compression test came back 170 across the board.



At this point, I'm pretty much reduced to guessing that one of the parts I put in was also bad - the MAF maybe? I'm out of ideas and hoping someone out there has a few (helpful ideas, not "shoot it and buy a Dodge" ideas. :) ) Thanks for any help!

Comments

  • edited September 2010
    Actually, the first thing that came to mind while I was reading your question was the MAF. But I doubt the replacement part is bad, and in fact the original part might have been okay. Instead of re-replacing the part, make sure the contacts for the mass air flow sensor are clean. Often the problem is not that the MAF is bad, but that the sensor and the connections are dirty. CRC Industries makes a specific cleaner for the part and connections. http://www.crcindustries.com/auto/content/prod_detail.aspx?S=Y&PN=05110
    Seems like you did or tested everything else, and the symptoms fit.
  • edited September 2010
    You don't mention actually checking the fuel rail pressure. Was the fuel pressure in fact measured and is it stable during driving conditions?

    You sure have been shot gunning this repair. Have you replaced the fuel pressure sensor/transducer and/or the fuel pump driver module?

    Keep us appraised of your progress on this.
  • edited September 2010
    I have suspected the MAF - it has come up a number of times reading about these types of problems. I actually replaced it with a reman. (only thing I could get at local parts store) - and have returned it a second time. No change. Possible the contacts are dirty, I will check and clean them. I've also considered just getting a MAF from the dealer, but I wince at the price if I'm not sure it is the problem.
  • edited September 2010
    I've considered the fuel pressure - I haven't checked it personally(I don't have the tool), but at least two of the shops I had it at assured me it was good. I'm not sure how to test it while driving - and the problem is worst when first started up.

    AFAIK, the fuel pressure sensor is integrated in the fuel pump module which I replaced (with a used one). The module (I believe) is part of the PCM, I don't think there is a separate driver. The only thing on the fuel rail in the engine is the fuel pressure dampener, which I have not replaced - it is not leaking, but I don't know how to test it to see if it has simply failed.
  • edited September 2010
    Since I posted this, I added a quart of Marvel Mystery Oil to the crankcase - nothing else. And since it has been getting worse the last couple weeks, but after I added the oil it actually seems to be getting better. No miracle cure, but it seems to be doing better. Any ideas of what this could mean? Sticky valves? Clogged lifters? Any way to diagnose this or fix it if it is the problem?
  • edited September 2010
    Why would you do that??
    Now you need an oil change too. A whole quart? MMO is something you used to squirt into the oil fill to mix with the oil to allegedly clean up deposits on the cylinders and even bearings and valves and whatnot, BEFORE just about every oil came mixed with thinner oils and detergents for just this exact purpose, and before every car began recommending exactly which oil blend to use!

    Since when does it even come in quarts?!?

    Marvel Mystery Oil is a very thin oil that again, in limited amounts may help clean up mostly carbon deposits and also other long chain molecule films or whatever else that might cling and bond with the metals in your engine. It would do this by getting very hot and melting and burning these deposits away.
    Most oils now do the same thing without ever compromising the protective properties of motor oil. You don't even have leaded gasoline anymore. The days of carbon deposits on the whatever, rings, pistons, valves, what have you, are gone.
    I notice you say it seems better after you added a quart of MMO. That might even make sense, but in the interim, you need an oil change back to your normal oil. I'm not even sure what my original suggestion was now. Just get an oil change, using the oil that the manufacturer recommends.
  • edited September 2010
    Did cleaning the contacts help? You already replaced the MAF, so I doubt that to be your problem. I would not recommend trying another MAF replacement, just that you make sure the part and contacts are clean.
  • edited October 2010
    Maybe you're confusing MMO with something else:

    (From their website) - (http://www.marvelmysteryoil.com/index.php/site/mmo/)
    "Marvel should be added to your engine oil at every oil change. In a traditional automobile engine with a 5 quart oil capacity, simply replace one of the engine oil quarts with a quart of Marvel. For your convenience, MM13R is the quart size of Marvel Mystery Oil? and can be found at most automotive parts and supply retailers and mass merchants. Marvel is also safe and effective to use with synthetic and synthetic-blend motor oils."

    Heck, you can buy it in anything from 16 oz to 55 gallon drums...

    Anyways, it did seem to run better, but the next day it was back to the same old popping and hesitating that it has always been doing. I then took it to the dealer nearby, and they told me that no doubt about it, my ignition coils were bad (1,5,6). I bit the bullet and bought 6 new ones from Advance Auto Parts. As I was swapping them out, I checked the spark plugs that the last mechanic installed and they were all gapped wrong - they were all at .040-.042, as I understand it it should be .054. Fixed that, replaced all coils. Since then, I haven't heard a pop or had it miss or hesitate at all! So something must be working right again.

    It still idles kinda rough, and after a trip of about 200 miles the CEL came on again - said misfire in cylinders 2 and 3. Grrr... The CEL went off again after a bit, and I haven't seen it since. Hoping to get it checked out more, but for the moment the worst seems to have been solved.
  • edited April 2011
    Escape misfire SOLVED:

    The problem is one or more defective coils. You see, the plastic that the body of the coil is manufactured with is of poor quality. After a while tiny cracks develop, sometimes invisible to the naked eye. Reach your fingers in there while the car is running. Chances are you will get zapped by touching one of the coils. This problem is exacerbated by wet weather.

    It gets even more confusing because the short in the system causes the PCM (powertrain control module) to go haywire. On interrogation, you may get multiple trouble codes (cylinder misfire, defective O2 sensors, etc.) when in fact, nothing else is wrong with the car.

    My advice:

    1. Clean and sand EVERY connection from the coil driver wires on down to the spark plugs.

    2. When installing new plugs, make sure: a)They are correctly gapped (.054 for 2003 V6 escape) and b)They are installed correctly with a SPARK PLUG SOCKET that has the proper rubber bushing inside to ensure the plug does not FALL into the hole (thus, affecting the gap.)

    3. Wrap EVERY coil in electrical tape, on up to the coil wires (a couple of inches.) This will require 2-3 rolls of electrical tape. Leave no part of the coil exposed.

    4. Disconnect the negative battery terminal and allow the car to sit for at least 5 minutes.

    One you reconnect the battery and start the car you will be able to determine whether or not there has been damage to the PCM. Hopefully, it runs smooth and the check engine light stays off. If you continue to get random trouble codes, you may need to install a new PCM. Contact your local dealer, and as always, get ready to be raped.
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