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Boneheaded move: MAP sensor shot?

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by pingd, Sep 29, 2019.

  1. pingd

    pingd Member

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    So I removed my MAP (Manifold Absolute Pressure) sensor from the throttle body and shot it with brake clean and used a Q-tip to clean it (kind of oily).
    Did I just kill it?
    What should have just used ... MAF cleaner? Electrical contact cleaner?
    (I did not realize it was the MAP sensor. I already cleaned the MAF sensor with MAF sensor cleaner.)

    Thank you!
     
  2. Raytheeagle

    Raytheeagle Senior Member

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    MAF sensor cleaner is what I have used with good success;).

    Remember that for next time and hope for the best now(y).
     
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  3. Montgomery

    Montgomery Senior Member

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    From what I have read in Priuschat, sensors should be cleaned with sensor cleaners. You may be correct that the sensor is now bad. Perhaps plugging it in and seeing if you throw any codes or christmas lights on the dashboard?
     
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  4. Rebound

    Rebound Senior Member

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    You shouldn’t have used brake cleaner, but that doesn’t mean it’s ruined. Just put it back in and see if it throws a code. I wouldn’t worry about it unless you get a code. You’re probably fine.
     
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  5. tankyuong

    tankyuong Senior Member

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    Should b fine
     
  6. Mendel Leisk

    Mendel Leisk Senior Member

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    The MAP sensor lives near the bottom of the intake manifold, and gets oily as heck. It's probably fine. If no error codes then for sure it's fine?

    FWIW I use CRC MAF sensor cleaner on it, whenever I have things opened up. And I have dabbed at it with a Q-Tip.
     
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  7. Mendel Leisk

    Mendel Leisk Senior Member

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    I think I did use brake cleaner, once, first time I tried cleaning it. IIRC it left it looking kinda whitish? It survived. I went out and got some MAF soon thereafter, went over it again.
     
  8. Rebound

    Rebound Senior Member

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    Now you’ve done it! Now you’ve done it! Your whole car could explode! Your whole neighborhood even!

    You aren’t supposed to touch it with a Q-Tip. Just let the MAP cleaner fluid dissolve whatever’s there and otherwise let it be.
     
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  9. Mendel Leisk

    Mendel Leisk Senior Member

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    Yeah the MAP sensor looks a lot more durable than the MAF sensor. The latter I sprayed once, was very careful with it, only used CRC MAF Sensor Cleaner, no touch. I don't think it needed it, looked perfectly clean. It is a very delicate looking item.

    The MAP sensor OTOH, looks like a relatively durable resistor of some sort, and invariably has an oil sheen, from the PCV valve, even with an OCC. Now I only spray it, with the CRC MAF sensor cleaner.

    They're both over $200 to replace, so yeah, be careful.

    (Think I used up my acronym quota for a week...)
     
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  10. pingd

    pingd Member

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    I'll remember to report back the final result ... hoping for the best ... as luck would have it ... I have a spare (of unknown state/quality)(came "free" with used 2010 intake manifold+throttle body+EGR pipe (ebay $120)).

    Right now I have my poor buddy all torn apart (wiper cowl, intake manifold, ICE coolant drain, TRYING to get that %$F#^! EGR cooler out!).

    Waiting for some parts + tools (should have known there'd be rust!)(should have taken notes on NutzAboutBolts videos!).
    Also, CRAP! - looks like oil is weeping on the engine backside, passenger side ... so probably the timing cover or crankshaft gasket? (need to read more about these two to figure it out ...)(not weeping bad at this point 153k)
     
    #10 pingd, Sep 30, 2019
    Last edited: Sep 30, 2019
  11. Mendel Leisk

    Mendel Leisk Senior Member

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    There's oil pressure sensor on the back wall of the engine too, that's been reported leaking here before.
     
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  12. pingd

    pingd Member

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    I wonder, are there "telltale signs" if it is the oil pressure sensor?
     
  13. Mendel Leisk

    Mendel Leisk Senior Member

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    Here's a Repair Manual excerpt on how to remove/test/replace. I see when installing there's a recommendation to apply a sealant. Looks like you can access by removing the right side wheel. It's not mentioned but you might also need to remove some wheel well liners, not sure. Or just throw in the towel: remove the wipers and cowl. I would try to get eyes on it first, before pulling too many parts, if possible: it's just one possibility.
     

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  14. Tim Jones

    Tim Jones Senior Member

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    I installed a catch can........works great...... think it was under $30.00
    Has oil in it every time I check it.....
    Guess I should look in the bottom of the intake to see if there is any oil there....
    239,000.......doesn't leak or burn any oil.....have cleaned the egr system......
    running 10w 40 synthetic oil......
    trani needs replaced.....whine getting louder.....
     
    #14 Tim Jones, Oct 6, 2019
    Last edited: Oct 6, 2019
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  15. Tim Jones

    Tim Jones Senior Member

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    I spent 5 hours cleaning the water cooled egr system..... it was dirty.....best thing to do let it sit in gas for a couple of days if you have the time.....
     
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  16. Mendel Leisk

    Mendel Leisk Senior Member

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    I found my oil catch can reduced the oil in the intake manifold. Not 100%, but it went from being something like 1/8" pool at the bottom, to just a sheen. Some of that might be spit-back from the intake ports: every time I took the intake manifold off I saw a tear of of oil under each port.