A new question is answered every 9 seconds

2002 Ford Explorer Sport Trac. 175k miles. Check Engine light on.

This answer was rated:

2002 Ford Explorer Sport Trac. 175k miles. Check Engine light on. Rough Idle. Random misfires at lmost any RPM or speed. Have replaced: Fuel Filter. EGR Valve and EGR Valve controler - Coil Pack - Plugs and wires. No visible or audible vacuum leaks. Interesting to not that I just started towing a trailer (4k of weight) and problem occured about 2 weeks after start of pulling the trailer. I am driving with OD turned off. Problem not as noticable when not towing the trailer so it leads me to believe that this problem has been going on for possibly longer than I think it has. Any ideas?
Hi thank you for your question I can hep.

Can you get me the code stored in the ECU? This will help pinpoint the problem.

Also did you replace these parts to fix the problem? Have you noticed and smoke from the exhaust?
Customer: replied 6 years ago.
I cleared the codes but I think they were 0301 0302. I do remember it said engine misfire bank 1 then engine misfire bank 2. Yes the parts I replaced were in an attempt to fix the problem. I felt thst misfire could mean bad plugs or wires. When that didnt work Auto Zone said to look for vacuum leak. Couldnt find one but I figured with as many miles as the truck has it wouldnt hurt to replace the EGR valve and controller. BTW when I disconnect the vacuum hoses from the control the engine idles alittle better.
P0301 = Cylinder #1 Misfire Detected
P0302 = Cylinder #2 Misfire Detected

These codes are saying the problem are related to #1 and #2 cylinder's. This could be related to the coil pack but it would be more then just 1 and 2.

From the info you gave about disconnecting the vacuum hoses.
This sounds like the Mass Airflow (MAF) sensors is either bad or dirty.

Airflow Meter/Sensor

Mass Airflow (MAF) sensors measure the weight and rate of air moving through a passage of a known volume or size. Typically, MAF sensors utilize hot wire or thick film technology. Signals generated may be analog or digital depending on manufacturer. As more air passes through the MAF sensor, the voltage or frequency increases proportionally. The EMS uses this information to calculate injector pulse-width and spark advance. Performance issues from MAF sensor failures range from no-start conditions to stalling, hesitation, stumble and improper air/fuel mixtures.

A faulty MAF sensor due to loose connections, bad grounds, high resistance in the circuit, or opens in the circuit can cause the following symptoms.

Related Symptoms
  • A no start condition
  • Stalls at idle
  • Surging of idle
  • Extended crank time when engine is cold
  • Hesitation
  • Stumble
  • Chuggle
  • Poor fuel economy

The location of the Mass Air Flow (MAF) sensor (3), the electrical connector (1) and the retaining bolt (2)

It is not recommended to try to clean the sensor but remove it from the air duck and see what it looks like. You can try vary carefully using brace cleaner or alcohol to clean it.

Hope this helps
david, Auto Service Technician
Category: Ford
Satisfied Customers: 1500
Experience: Certified Master Technician,Certified in diesel & gasoline engines
david and 6 other Ford Specialists are ready to help you
Ask david Your Own Question
david , Auto Service Technician
Category: Ford
Satisfied Customers: 1500
Experience:  Certified Master Technician,Certified in diesel & gasoline engines
Type Your Ford Question Here...
david is online now
How JustAnswer Works:
  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site.
    Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.

What Customers are Saying:

  • AlvinC answered a question about my Ford truck that only someone with an in-depth knowledge of his subject would have known what was going on. Rich D USA
< Previous | Next >
  • AlvinC answered a question about my Ford truck that only someone with an in-depth knowledge of his subject would have known what was going on. Rich D USA
  • Because of your expertise, you armed me with enough ammunition to win the battle with the dealer. They are installing a fuel filter and fuel pump at no charge to me. Molly USA
  • I needed help with my car on Saturday morning....got a response in 5 minutes, and it was the perfect solution. Thanks again to your service. Jason V. Kirkland, WA
  • I do know, after going though this with JustAnswer, that I can somewhat trust my mechanic but I will always contact you prior to going there. BR New Jersey
  • I would (and have) recommend your site to others I was quite satisfied with the quality of the information received, the professional with whom I interacted, and the quick response time. Thanks, and be sure that I'll be back whenever I need a question answered in a hurry. Stephanie P Elm City, NC
  • used your service this weekend with "Trecers" help. thank you ,thank you, thank you. replaced an A/C fan motor. Local Auto Zone had part. $15.00 "tracer" fee and $40.00 for parts, I saved several hundreds of dollers at a shop. i will recommend you and use you in the future. David L. Richmond, TX
  • 9 dollars, 2 hours of my time, and I drove away. Your diagnosis was right on the mark. Thank you so much. Phil Marysville, CA

JustAnswer in the News:

Ask-a-doc Web sites: If you've got a quick question, you can try to get an answer from sites that say they have various specialists on hand to give quick answers... Justanswer.com.
JustAnswer.com...has seen a spike since October in legal questions from readers about layoffs, unemployment and severance.
Web sites like justanswer.com/legal
...leave nothing to chance.
Traffic on JustAnswer rose 14 percent...and had nearly 400,000 page views in 30 days...inquiries related to stress, high blood pressure, drinking and heart pain jumped 33 percent.
Tory Johnson, GMA Workplace Contributor, discusses work-from-home jobs, such as JustAnswer in which verified Experts answer people’s questions.
I will tell you that...the things you have to go through to be an Expert are quite rigorous.

Meet The Experts:

  • Ron


    ASE Certified Technician

    Satisfied Customers:

    23 years with Ford specializing in drivability and electrical and AC. Ford certs and ASE Certs
< Last | Next >
  • http://ww2.justanswer.com/uploads/FO/fordguyu/2015-7-7_172556_onnieew.64x64.jpg Ron's Avatar


    ASE Certified Technician

    Satisfied Customers:

    23 years with Ford specializing in drivability and electrical and AC. Ford certs and ASE Certs
  • http://ww2.justanswer.com/uploads/MU/muddyford/2012-6-13_1204_1.64x64.png Chris (aka- Moose)'s Avatar

    Chris (aka- Moose)


    Satisfied Customers:

    16 years experience
  • http://ww2.justanswer.com/uploads/JM/jmcdo28/2012-2-23_01655_resized.64x64.jpg John Mc's Avatar

    John Mc

    Ford Technician

    Satisfied Customers:

    19 years Ford Lincoln Mercury experience
  • http://ww2.justanswer.com/uploads/wmarti7/2009-4-18_04332_Avatar.jpg Chuck's Avatar


    ASE Certified Technician

    Satisfied Customers:

    33 Years Experience,Ford Senior Master,ASE Master,L1 Advanced Engine Performance
  • http://ww2.justanswer.com/uploads/BL/Bluegorilla/2012-6-21_16298_cam.64x64.JPG Cam's Avatar


    Journeyman Automotive Technician

    Satisfied Customers:

    GM Grand Master Technician 2007. 14 years Automotive experience.
  • http://ww2.justanswer.com/uploads/CR/crzydrvr00/2013-11-3_12123_246347.64x64.jpg Richard's Avatar


    ASE Certified Technician

    Satisfied Customers:

    12 years at a Ford Lincoln/Mercury and Jaguar dealer as a technician and shop foreman.
  • http://ww2.justanswer.com/uploads/BA/baddad1/2014-4-1_23659_avatar.64x64.jpg Mike V.'s Avatar

    Mike V.

    Auto Service Technician

    Satisfied Customers:

    25 years experience on all makes and models, Licensed NYS Inspector.