Page 2 of 3 FirstFirst 123 LastLast
Results 11 to 20 of 22

Thread: What does this tube do?

  1. #11
    Senior Member
    Join Date
    Feb 2021
    Location
    Toronto
    Country
    Canada
    Posts
    1,024
    Thanks
    1,536
    Thanked 240 Times in 199 Posts
    Quote Originally Posted by Eggman View Post
    This is interesting. Forgive my ignorance, but how is this a test of a positive crankcase ventilation valve? Aren't there other ways to test the valve or the ventilation circuit? How about just removing the hose and capping the port at the manifold? (Which makes me think if this may be a case of a cracked intake manifold...)
    .
    yes the linked thread describes testing it via shaking it and hearing for a rattle and by looking inside the valve at how clean it is. Yes you could also try and remove the hose and cap the valve or port at the manifold for testing. Flooring it would in theory completely open the valve and then when releasing the accelerator if the valve were to stick open may mimic the effects of a vacuum leak and induce the rough idle.

    Quote Originally Posted by Eggman View Post
    Also, are you suggesting flooring the engine unloaded (I assume you mean with the engine running) and just flooring the accelerator pedal for "a few seconds", making the engine race at it's rev limit? Doesn't that put engine at risk of damage? I've never done this, just wondering if this is a common troubleshooting technique that I'm not aware of. Although it sounds like what I've heard called an Italian Tune-Up...
    Ive done this plenty of times (with the cold engine light off) and have not had any issues nor do i have any concerns with the practice, the rev limiter does a great job at protecting the engine.

    Quote Originally Posted by Eggman View Post
    If there's an air leak at the intake manifold, wouldn't that upset the air-fuel ratio? If that's the case, one could monitor this by watching the A/F ratio using the OBD port as I recall doing this with my phone.
    Dependent on whether or not OP has a MAF sensor this may not be very accurate


    please consider checking out my Mirage related youtube channel: https://www.youtube.com/channel/UC6c...IEViRFw/videos

  2. #12
    Member
    Join Date
    Mar 2023
    Location
    Iran
    Country
    Iran
    Posts
    34
    Thanks
    6
    Thanked 7 Times in 5 Posts
    Quote Originally Posted by mohammad View Post

    Dependent on whether or not OP has a MAF sensor this may not be very accurate
    My car only has the MAP sensor not the MAF


    I will take a look at the PCV system but nowadays I'm a bit busy so I will update soon

  3. The Following User Says Thank You to nimas1377 For This Useful Post:

    mohammad (11-10-2023)

  4. #13
    Member
    Join Date
    Mar 2023
    Location
    Iran
    Country
    Iran
    Posts
    34
    Thanks
    6
    Thanked 7 Times in 5 Posts
    So I checked the pcv today and it was not so free when I shook it but I managed to clean it with carb cleaner and also I found a tube that wasn’t connected to anything so can you please verify if it is like that from factory?

    Name:  IMG_6113.jpg
Views: 144
Size:  86.6 KB

    The tube is exactly below the one I asked the question and it’s short and I comes from under it gearbox I assume

  5. #14
    Senior Member
    Join Date
    May 2014
    Location
    Country is Europe, state is Germany
    Country
    Germany
    Posts
    1,686
    Thanks
    227
    Thanked 1,139 Times in 661 Posts
    The picture is far from ideal. I pressume it is the water discharge tube for condensation from the airconditioning.

  6. #15
    Member
    Join Date
    Mar 2023
    Location
    Iran
    Country
    Iran
    Posts
    34
    Thanks
    6
    Thanked 7 Times in 5 Posts
    Quote Originally Posted by foama View Post
    The picture is far from ideal. I pressume it is the water discharge tube for condensation from the airconditioning.
    You are right let me show it with more photos

    Name:  IMG_6114.jpg
Views: 138
Size:  98.1 KB
    So this is my engine bay and next photo I will go closer to the marked part

    Name:  IMG_6115.jpg
Views: 138
Size:  93.9 KB
    And this is the tube I asked in this thread so for next photo I will push it aside and see under it and as you can see it will be a thin tube under just hanging there
    Name:  IMG_6116.jpg
Views: 138
Size:  91.2 KB
    I will hold it with my hand in the next photo
    Name:  IMG_6117.jpg
Views: 137
Size:  91.2 KB

  7. #16
    It's a vent hose for the transmission.

        __________________________________________

        click to view fuel log View my fuel log 2014 Mirage SE wussie cvt edition. 1.2 automatic: 37.7 mpg (US) ... 16.0 km/L ... 6.2 L/100 km ... 45.3 mpg (Imp)


  8. The Following 2 Users Say Thank You to Fummins For This Useful Post:

    mohammad (11-17-2023),nimas1377 (11-17-2023)

  9. #17
    Senior Member
    Join Date
    Feb 2021
    Location
    Toronto
    Country
    Canada
    Posts
    1,024
    Thanks
    1,536
    Thanked 240 Times in 199 Posts
    Fummins is correct.
    please consider checking out my Mirage related youtube channel: https://www.youtube.com/channel/UC6c...IEViRFw/videos

  10. The Following User Says Thank You to mohammad For This Useful Post:

    nimas1377 (11-18-2023)

  11. #18
    Member
    Join Date
    Mar 2023
    Location
    Iran
    Country
    Iran
    Posts
    34
    Thanks
    6
    Thanked 7 Times in 5 Posts
    So I cleaned my pcv valve but still I have the problem (rough idle some times)
    But still I think it might be the pcv valve so How can I 100% test the pcv valve when opened so I can verify if it's causing the problem or not

    If needed I have to dig deep to find a replacement but It is an option if it is faulty

  12. #19
    Senior Member
    Join Date
    Feb 2021
    Location
    Toronto
    Country
    Canada
    Posts
    1,024
    Thanks
    1,536
    Thanked 240 Times in 199 Posts
    Quote Originally Posted by nimas1377 View Post
    So I cleaned my pcv valve but still I have the problem (rough idle some times)
    But still I think it might be the pcv valve so How can I 100% test the pcv valve when opened so I can verify if it's causing the problem or not

    If needed I have to dig deep to find a replacement but It is an option if it is faulty
    The PCV valve is not unique to the car you can find plenty of tips on how to test the valve on Google and YouTube. In theory with the hose or valve off if you plug the hole in the engine block or cover the valve with a balloon type thing you can test and see if the rough idle occurs. If the problem is fixed them you know it was a PCV valve problem.
    please consider checking out my Mirage related youtube channel: https://www.youtube.com/channel/UC6c...IEViRFw/videos

  13. #20
    Moderator Eggman's Avatar
    Join Date
    Sep 2015
    Location
    Cleveland, Ohio
    Country
    United States
    Posts
    10,077
    Thanks
    4,021
    Thanked 2,762 Times in 2,086 Posts
    Quote Originally Posted by mohammad View Post
    In theory with the hose or valve off if you plug the hole in the engine block or cover the valve with a balloon type thing you can test and see if the rough idle occurs.
    Do you mean block the air intake side rather than the engine or valve cover outlet?


        __________________________________________

        click to view fuel log View my fuel log 2015 Mirage ES 1.2 manual: 49.6 mpg (US) ... 21.1 km/L ... 4.7 L/100 km ... 59.5 mpg (Imp)


Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •