P0300, P0301, P0302, P0103

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by Triparadox, Mar 12, 2019.

  1. Triparadox

    Triparadox Junior Member

    Joined:
    Mar 12, 2019
    36
    6
    0
    Location:
    California
    Vehicle:
    2010 Prius
    Model:
    Three
    I just purchased a car not very long ago (within one month) and it showed me an engine light indicator. Once plugged with OBD2, it appeared that there were multiple misfiring from Cyl. 1 and Cyl. 2. I swapped both spark plugs and ignition coil as follow:

    1 to 4
    2 to 3

    I resetted the indicator. Today it came back again, still with Cyl. 1 and Cyl. 2 with an additional P0103 (MAF). Can anyone give me some suggestion???
     
  2. The Critic

    The Critic Resident Critic

    Joined:
    Oct 28, 2005
    2,439
    860
    0
    Location:
    Walnut Creek, CA
    Vehicle:
    2011 Prius
    Model:
    Three
    The misfires, at least at this point, may be due to the MAF issue. Address the MAF fault before addressing the misfires. If you have access to a scanner, check to make sure that you are seeing at least 1.8 g/sec at idle. There are probably better ways of testing a MAF but regardless, you need to address the MAF problem before the misfires.
     
    Raytheeagle likes this.
  3. bisco

    bisco cookie crumbler

    Joined:
    May 11, 2005
    75,996
    31,773
    0
    Location:
    boston
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    you're gonna get confused with two threads on the same problem
     
    Raytheeagle and The Critic like this.
  4. Triparadox

    Triparadox Junior Member

    Joined:
    Mar 12, 2019
    36
    6
    0
    Location:
    California
    Vehicle:
    2010 Prius
    Model:
    Three
    Sure, I'll try to clean it when I have the time. I also tried to find the 2010 Prius cleaning MAF guidance.. No luck until now.. Mind helping me on that one?

    Yes. I was at phone the first time, so I didn't really see the troubleshoot section.
     
    #4 Triparadox, Mar 13, 2019
    Last edited by a moderator: Mar 14, 2019
  5. Triparadox

    Triparadox Junior Member

    Joined:
    Mar 12, 2019
    36
    6
    0
    Location:
    California
    Vehicle:
    2010 Prius
    Model:
    Three

    BTW there's an information I forget to add:

    Sometimes, when I start the engine up, there will be rattling vibration and sound for the first couple seconds (longest one was around 9 seconds). It's not always. If after that I turn off and turn the engine on again, it won't rattle. After a long period of time, there's a high chance it will rattle, but again, not always... like 75% chance.
     
  6. The Critic

    The Critic Resident Critic

    Joined:
    Oct 28, 2005
    2,439
    860
    0
    Location:
    Walnut Creek, CA
    Vehicle:
    2011 Prius
    Model:
    Three
    The MAF sensor is located on the backside of the air intake tube. IIRC it uses phillips screws. Remove and clean if you desire, but I have never had success with cleaning MAFs.

    How's your coolant level? In my experience if this engine suddenly develops a start-up rattle at high mileage, there is a high probability of headgasket failure.
     
    Raytheeagle likes this.
  7. Triparadox

    Triparadox Junior Member

    Joined:
    Mar 12, 2019
    36
    6
    0
    Location:
    California
    Vehicle:
    2010 Prius
    Model:
    Three
    I just refilled the coolant to the appropriate level last couple days.. I'll see tomorrow. What if it actually drops below the gauge? Is it head gasket failure? Is this easy to fix? Expensive?
     
  8. The Critic

    The Critic Resident Critic

    Joined:
    Oct 28, 2005
    2,439
    860
    0
    Location:
    Walnut Creek, CA
    Vehicle:
    2011 Prius
    Model:
    Three
    Not sure which "gauge" you are referring to. The easiest way to check for headgasket failure on these engines is to pressurize the cooling system overnight (with a pressure tester), then remove the spark plugs. Then use an inspection camera to inspect the tops of the pistons for signs of coolant intrusion.
     
    Raytheeagle likes this.
  9. Triparadox

    Triparadox Junior Member

    Joined:
    Mar 12, 2019
    36
    6
    0
    Location:
    California
    Vehicle:
    2010 Prius
    Model:
    Three
    I do not have the pressure tester... I'm complete beginner with limited access to tools.
     
  10. Triparadox

    Triparadox Junior Member

    Joined:
    Mar 12, 2019
    36
    6
    0
    Location:
    California
    Vehicle:
    2010 Prius
    Model:
    Three
    Update: I just checked the coolant reservoir level. It's below LOW now even though I'm pretty sure I filled it up to the appropriate level couple days ago.
     
  11. FnRedPrius

    FnRedPrius Junior Member

    Joined:
    Jan 10, 2019
    58
    56
    0
    Location:
    Pilot, NC
    Vehicle:
    2010 Prius
    Model:
    III
    Coolant loss isn't always consistent with a head gasket failure. Ours went thru almost a gallon it just over a week, but since the problem became apparent in early December total loss has been about 2 gallons. As @The Critic said, wet piston tops after a cold soak will probably be the best indication.
     
Loading...