DIY Engine Compression Test!!!
Page 1 of 2 12 LastLast
Results 1 to 15 of 16

This is a discussion on DIY Engine Compression Test!!! within the Maintenance, service, and repair forums, part of the Tutorials & DIY category; Spent 45 min performing compression test with compressiont tester today. Make sure to perform test when car is warm. ...

  1. #1
    Registered User WRXreX's Avatar
    Join Date
    Mar 2002
    Location
    NY
    Posts
    997

    DIY Engine Compression Test!!!

    Spent 45 min performing compression test with $25 compressiont tester today. Make sure to perform test when car is warm.

    2002 WRX with 90k miles
    Mods: VF34 @ 19psi protuned 282whp/272wtq
    JDM STI TMIC
    Maddad v2 DP & whisper catback
    One step colder NGK platinum plugs
    Stock intake with K&N panel filter
    German castrol oil

    1. Remove stock intake box, etc:



    2. Remove 12mm bolt in order to remove coil pack from each cylinder:




    3. Remove spark plugs using 5/8" long socket with an extension



    4. Coil pack and spark plugs removed:

  2. Remove Advertisements
    ClubWRX.net
    Advertisements
     

  3. #2
    Registered User WRXreX's Avatar
    Join Date
    Mar 2002
    Location
    NY
    Posts
    997
    5. Pull ignition fuse
    - Fuse remover is located next to battery:



    6. Connect compression tester into each cylinder:



    7. Now it's time to crank the engine with FULL wide open throttle. Crank the engine 6 times.


    8. Repeat the test for each cylinder and pray numbers come out good:





    :banana:

  4. #3
    Registered User
    Join Date
    Oct 2008
    Posts
    1

    Good numbers

    Those are GOOD numbers, consistent - are you happy with them ?

    Thanks for a great article.

  5. #4
    The Default One SeattleJeremy's Avatar
    Join Date
    Jul 2004
    Location
    Seattle, WA
    Posts
    4,488
    Very cool!
    Where did you get the compression tester?

  6. #5
    Registered User WRXreX's Avatar
    Join Date
    Mar 2002
    Location
    NY
    Posts
    997
    Got it from advance auto part for $25.

  7. #6
    Registered User
    Join Date
    Jul 2007
    Posts
    20
    What do you mean 6 times? Hold constantly for 6 cranks, or hold, let go, hold, let go, etc. 6 times?

  8. #7
    Registered User FITwagun's Avatar
    Join Date
    Aug 2007
    Location
    Findlay,OH
    Posts
    60
    What about releasing the fuel pressure? Wont doing this without releasing the fuel pressure leave raw fuel in the combustion chambers, and therefore altering test results? thanks

  9. #8
    Registered User
    Join Date
    Aug 2009
    Posts
    4
    Not that difficult to solve. Just make sure you remove the fuse that runs your fuel pump. Done it on Honda's half a dozen times already

  10. #9
    The Default One SeattleJeremy's Avatar
    Join Date
    Jul 2004
    Location
    Seattle, WA
    Posts
    4,488
    Quote Originally Posted by FITwagun View Post
    What about releasing the fuel pressure? Wont doing this without releasing the fuel pressure leave raw fuel in the combustion chambers, and therefore altering test results? thanks
    I know this is late, but according to the thread below #11 is the ignition system and fuel pump fuse.
    http://www.scoobymods.com/help_02_wrx_fuse-t5024.html

  11. #10
    Registered User T.J.'s Avatar
    Join Date
    Oct 2002
    Location
    on a boat...
    Posts
    821
    Nice. I will do this when I replace my spark plugs soon. Thanks for the tips.

    T.J.
    200,000 mile club.

    Old Irish adage: "Do not resent growing old. Many are denied the privilege."

  12. #11
    Registered User tarmacsti's Avatar
    Join Date
    Dec 2007
    Location
    South Africa, Jo'burg
    Posts
    862
    Leaving spark plugs on the ground like that aint a good idea... I left mine on the ground once and accidentally stepped on them... 1 broke... (but it was dumb i know) still prevention is better...
    **__The Hawk-Eye Alliance__**
    Member #0135

  13. #12
    Registered User
    Join Date
    Jul 2012
    Posts
    71
    Total thread resurrection here, but when I was trying to do a compression test on my outback, I found it was a total PITA to get the compression tester with the flexible hose threaded into the spark plug hole.

    Does anyone have tips on how to do that? Do you need an adapter to make it easier?

  14. #13
    Moderator T0rque's Avatar
    Join Date
    Dec 2004
    Location
    Medford, Oregon
    Posts
    25,521
    I Support ClubWRX
    You could use an adapter if you could find one that would get into the hole. Your better off trying to just get the tester screwed in correctly. Better more costly gauges have a little better hose making it easier to thread than cheaper gauges with cheaper hoses. Good luck


    Lead Wrench @ WTF Tuning, LLC

  15. #14
    Registered User
    Join Date
    Jul 2012
    Posts
    71
    Yeah I know there are testers that come with a number of adapters, maybe I'll try one o those out, see if it makes it easier.

  16. #15
    Registered User
    Join Date
    Jul 2012
    Posts
    71
    Quote Originally Posted by T0rque View Post
    You could use an adapter if you could find one that would get into the hole. Your better off trying to just get the tester screwed in correctly. Better more costly gauges have a little better hose making it easier to thread than cheaper gauges with cheaper hoses. Good luck
    Compression test tips - NASIOC

    This guy uses spark plug anti foulers to put some length on his, fantastic idea I think.

Page 1 of 2 12 LastLast

Posting Permissions

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