1. Welcome to Tacoma World!

    You are currently viewing as a guest! To get full-access, you need to register for a FREE account.

    As a registered member, you’ll be able to:
    • Participate in all Tacoma discussion topics
    • Communicate privately with other Tacoma owners from around the world
    • Post your own photos in our Members Gallery
    • Access all special features of the site

P0300 Error Code but only when it rains?

Discussion in 'Technical Chat' started by Graham, Apr 8, 2009.

  1. Apr 8, 2009 at 12:58 PM
    #1
    Graham

    Graham [OP] Pay it Forward

    Joined:
    Apr 8, 2009
    Member:
    #15723
    Messages:
    662
    Gender:
    Male
    Western New York
    Vehicle:
    2005 4x4 TRD Black V6 6 speed manual
    Re-occuring P0300 Error code but only when it rains?
    Hi, New to the forum! Absolutely love it. I've got a 2005 V6 manual 4x4 Tacoma, 145K miles mostly highway with off road mixed in for fun.

    My issue is I randomly get a check engine light notification with an associated P0300 code. I know what it means and have been to 2 different dealerships and 2 respected independent mechanics who can't find the issue. They change the plugs, check the timing, clean the MAF, but don't really give me a true root cause to fix once and for all. This has happened probably 3 times over the past 2 years. Latest instance was monday on a run to Lewisburg, PA. What happens is the engine gives a hesitation slight to severe at highway speeds, I can press the accelerator to the floor with no increase in speed and then the check engine light comes on with the engine running in a rough fashion, it feels sputtery and weak. I usually pull over for 15 to 20 minutes with the engine off. Start it up again, the check engine light is on but the engine is now operating fine with plenty of power. The one constant when this happens is that it is always raining when this happens and I am operating in cruise control mode. I have never had it happen when I am driving in cruise control and it is dry out. WTF? Any suggestions?

    Thanks,
    Graham
     
  2. Apr 8, 2009 at 2:05 PM
    #2
    Janster

    Janster Old & Forgetful

    Joined:
    Mar 25, 2007
    Member:
    #1138
    Messages:
    14,339
    Gender:
    Female
    First Name:
    Jandy
    Lancaster, PA
    Vehicle:
    2016 GMC Canyon SLT w/ LineX and....
    Hmm double post....

    Double reply :D

    If you've had it to two different dealerships and two other mechanics, then I'd say you're pretty much SCREWED.

    Because honestly, if 4 different shops can't figure it out - that's pretty damn pathetic.
    P0300 Random/Multiple Cylinder Misfire Detected

    Did you do any researching online yet?
    Here's some reading for ya to get you started. Google is your friend.
    http://www.parksoffroad.com/tacomamo...e/cip0300p.pdf
    http://www.obd-codes.com/forums/view...php?f=1&t=3406
     
  3. Apr 8, 2009 at 8:33 PM
    #3
    Graham

    Graham [OP] Pay it Forward

    Joined:
    Apr 8, 2009
    Member:
    #15723
    Messages:
    662
    Gender:
    Male
    Western New York
    Vehicle:
    2005 4x4 TRD Black V6 6 speed manual
    Sorry for the time lag, I was out to dinner with my parents.

    Double post was the quick realization that the first post was in the lighting forum. Oops, doesn't pay to hurry.

    Thanks for the info and sites. I will look through them for more info. I have done lots of online research and it points to the temporary fixes that have been done and well temporary. Only one reference speaks to inspecting and replacing the EVAP. I'm not sure what that is. Can you give me the basic process? I am starting to wonder if the fault is farther downstream in the engine exhaust system. Does the EVAP interact closely here?

    Any thoughts is helpful. Thanks.
     
  4. Apr 9, 2009 at 3:42 AM
    #4
    Janster

    Janster Old & Forgetful

    Joined:
    Mar 25, 2007
    Member:
    #1138
    Messages:
    14,339
    Gender:
    Female
    First Name:
    Jandy
    Lancaster, PA
    Vehicle:
    2016 GMC Canyon SLT w/ LineX and....
    I can't personally help - as I would have to research and learn about it myself.

    That's how I've learned things over the years, lots & lots of research and getting out there and doing the work yourself.

    Do you have any shop repair manuals for your truck?
    You can go here and find what you need (scroll down)
     
  5. Apr 9, 2009 at 11:30 AM
    #5
    Graham

    Graham [OP] Pay it Forward

    Joined:
    Apr 8, 2009
    Member:
    #15723
    Messages:
    662
    Gender:
    Male
    Western New York
    Vehicle:
    2005 4x4 TRD Black V6 6 speed manual
    Thanks again for the link.

    I think it's time for me to start digging into this instead of relying on mechanics. I have fixed alot of cars when I was younger but as I moved up the economic bracket I have paid folks to do it with good luck so far.
    This situation is calling for me to work it out myself.

    Stay tuned.
     
  6. Apr 9, 2009 at 11:41 AM
    #6
    Janster

    Janster Old & Forgetful

    Joined:
    Mar 25, 2007
    Member:
    #1138
    Messages:
    14,339
    Gender:
    Female
    First Name:
    Jandy
    Lancaster, PA
    Vehicle:
    2016 GMC Canyon SLT w/ LineX and....
    Keep us updated! I know sometimes things are a royal pain in the butt to figure out. That's the worst part - troubleshooting.

    Good Luck!
     
  7. Apr 9, 2009 at 12:22 PM
    #7
    SC4333

    SC4333 Well-Known Member

    Joined:
    Dec 9, 2008
    Member:
    #11412
    Messages:
    2,887
    Gender:
    Male
    First Name:
    Grant
    FL
    Vehicle:
    SOLD - 2016 TRD Off-Road 4x4 DCSB
    If you haven't already found what you were looking for with Janster's post, here is where you need to be.


    In this particular instance, without an advanced scan tool that runs in real time you will be at quite a disadvantage. The majority of causes for a simultaneous multiple cylinder misfire require either a factory/snap-on type scan tool, or an oscilloscope to diagnose. Start with the simple stuff and work you way up.

    I have the feeling there is a problem with either your MAF sensor, or possibly a short in the main wiring harness. Especially being that it only occures in raining situations.
     
  8. Dec 18, 2010 at 8:46 PM
    #8
    Graham

    Graham [OP] Pay it Forward

    Joined:
    Apr 8, 2009
    Member:
    #15723
    Messages:
    662
    Gender:
    Male
    Western New York
    Vehicle:
    2005 4x4 TRD Black V6 6 speed manual
    Can't believe I never finished this lead? Sorry for being a toad!

    So, After a few more rainstorms with this situation, I was racking my brain for events with the vehicle that may indicate when this alarming engine hesitation first occurred. It came to me that a that the hesitation began after a mud run on a track in southern New Hampshire.

    It was spring and the rains had been full on New England coastal dumps. This run is actually a named dirt side road with a 3 mile extension through a bog. Conditions ran from easy pine covered runs to full on stop and measure the depth of the water ahead moments. It was towards the end of this run while following my buddy in his stripped and jacked jeep that I ran through a deep hole and pulled up a downed sapling through my front right wheel well.

    It jammed in hard and forced me to an immediate stop. I found the sapling broken and spun up and over the wheel well and wedge tightly in plastic liner. I pulled, pushed, ripped and tore the offending tree out and brought a 8" portion of the liner with it. Thought nothing off it since I didn't think it would hurt anything and its a truck after all. Adds character right?

    Well, move forward to May of 09 the time of my original post. I finally wanted to get it fixed since I noticed that this opening brought an inordinate volume of road material into the engine well. I cleaned everything up and decided to change the air filter for the 1st time in a while. I had been lazy and paid jiffylube to do the oil/air routine. I've changed this practice bc I like the work on the vehicle not bc of the oil change place.

    When I pulled the filter it was brown and black with road crap. Whoah!! What is causing this. Follow the air flow to its source. The wheel well on my Tacoma. Directly on the body above where my liner is the air intake port for the engine. With out the liner the air filter was taking full assualt from moisture and material thrown up threw the wheel well and into the port, which based upon the weather I drove through was alot.

    I replaced the wheel well liner completely and overhauled the engine. Runs beautifully now!
     

Products Discussed in

To Top