Low compression

Discussion in 'Modifications And Maintenance' started by subaruordie, Jun 16, 2012.

  1. subaruordie
    Offline

    subaruordie Well-Known Member

    Likes Received:
    59
    Trophy Points:
    113
    The other day I decided to change my spark plugs because I had no clue when they were done last as I bought the car last august. I figured I should do a compression test while I am at it just to see where i was sitting. So I rented a tester from O'Riellys. The results made me kind of nervous. cylinder 4 is really low.

    1- 62
    3-65
    4-37
    2-70

    My car is a 2003 WRX with 180,000 miles.
    Mods include : Grimmspeed downpipe, grimmspeed EBC, srs exhaust and Nuke stage 2 tune.

    The car has run flawlessly since the day I bought it. It has never had a sign of low compression and hasn't thrown any codes. Its even idling a lot lower after changing the plugs.Should I be worried about this low compression? Is there any preventative maintenance I can do or do I just have to sit back and wait for something to go wrong? I have seen some short blocks showing up lately so i have been considering a Hybrid build but as a poor college student I am not sure it would be worth it right now. Any Ideas?



    Thanks in advance for any feedback
    -Josh
     
    subaruordie, Jun 16, 2012
    #1
  2. Nuke
    Offline

    Nuke Well-Known Member

    Likes Received:
    814
    Trophy Points:
    348
    Um those are really low # for ALL the cylonder. Sure you did it right?
    Car would run like ass if those #s were correct
     
    Nuke, Jun 16, 2012
    #2
  3. subaruordie
    Offline

    subaruordie Well-Known Member

    Likes Received:
    59
    Trophy Points:
    113
    I read a bunch of threads on how to Do it over on NASIOC but I could of done it wrong. This is the thread i followed and the tester looks the exact same.
    http://forums.nasioc.com/forums/showthread.php?t=1615288&highlight=diy compression test

    The one thing I did not follow on this thread is that I didn't perform the test with a warm engine. The employee at oreillys told me to do it after its been sitting awhile. Could this be my problem?

    A friend said that oriellys testers are horrible. I figured horrible tester or not the fluctuating numbers weren't good.
     
    subaruordie, Jun 16, 2012
    #3
  4. ShortytheFirefighter
    Offline

    ShortytheFirefighter Pokemans. I has none.

    Likes Received:
    1,571
    Trophy Points:
    398
    Those numbers all look way off, Nuke is right. If those are correct your car wouldn't be running right at all.
     
    ShortytheFirefighter, Jun 16, 2012
    #4
  5. subaruordie
    Offline

    subaruordie Well-Known Member

    Likes Received:
    59
    Trophy Points:
    113
    Alright. I will do the test again. This time I will do it when the engine is warm. Thanks!
     
    subaruordie, Jun 16, 2012
    #5
  6. KA-T_240
    Offline

    KA-T_240 Well-Known Member

    Likes Received:
    223
    Trophy Points:
    248
    How long were you cranking it?
     
    KA-T_240, Jun 17, 2012
    #6
  7. tangledupinblu
    Offline

    tangledupinblu Event Coordinator Staff Member

    Likes Received:
    9,058
    Trophy Points:
    573
    Have the exhuast vlaves ever been relashed in the 180,000 miles? You should get them done. Burnt exhaust valves on the 2.0L are common when valve relashing is overlooked/forgotten about.

    And agreed on all cylinders looking too low.
     
    tangledupinblu, Jun 17, 2012
    #7
  8. subaruordie
    Offline

    subaruordie Well-Known Member

    Likes Received:
    59
    Trophy Points:
    113
    I cranked on it for 6 seconds and I did each cylinder 3 times just to make sure my results were consistent.

    As far as the exhaust valves I'm not really sure. I purchased the car from justin grimm's father so I'll have to give him a call and ask. I don't think he had the car very long though. The person who owned it before him had all work done at a dealership in lacrosse so I'll call them and see what they have on record.
     
    subaruordie, Jun 17, 2012
    #8