Username or Email Address
Do you already have an account?
Forgot your password?
  • Log in or Sign up

    VWVortex


    Results 1 to 13 of 13

    Thread: DIY: How to do a Compression Test

    1. 11-01-2007 07:48 AM #1
      Compression Test directly from Bentley Manual.

      1. Release locking pins for engine cover by turning 90 degrees. Remove the cover completely.

      2. Warm up engine until it is a minimum of 30 degrees Celsius (60 degrees F) and switch ignition off.

      3. Disconnect 4 pin harness connectors from all ignition coils and
      remove ignition coils (Place them in a way that you know which ones are for each cylinder). If you have an AWD engine code unbolt the coils from the head and remove the vacuum reservoir (canister).. If you have an AWW or AWP engine code just remove the coils.

      4. Use compressed air to clear area around spark plugs. Remove all spark plugs and lay aside in an order that you remember which one goes to each cylinder.

      5. Remove fuse #32 for voltage supply to injectors (in car)

      6. Fit compression tester into spark plug hole.

      7. Have a helper - Depress clutch pedal fully, Put transmission in either park or neutral, Depress the accelerator pedal to floor, Crank engine over with starter motor. Crank a minimum of 4 to 5 revolutions.

      8. Record readings from each cylinder in gauge and repeat procedure for each cylinder.

      9. Compare readings to these specifications. New Cylinders (145-203 psi) Wear limit (102 psi) Maximum difference between cylinders 44 psi

      10. When all cylinders have been checked, reinstall spark plugs and ignition coils, connect harness connectors for coils and reinstall fuse #32. Reinstall fuse panel.

      NOTES Cranking engine with ignition system disabled and components disconnected will cause Diagnostic trouble codes (DTC's) to be stored in engine management system memory. You must clear these codes.

      Tightening Torques Spark plug to cylinder head - 22 ft/lbs

      Tightening Torques Ignition coil to cylinder head (If bolt down coils) - 7 ft/lbs.

      Enjoy !


    2. Member theswoleguy's Avatar
      Join Date
      Jan 24th, 2006
      Location
      Atlanta, GA
      Posts
      7,831
      Vehicles
      A few...
      11-01-2007 08:21 AM #2

      now someone explain the other little things you can do while compression testing. IE: teaspoon of oil in the cylinder to check for bad rings

      Project GTi-R:. '04 R32 Chassis w/ 1.8t transplant in the werks
      '01 Audi TTQ Roadster: QED motor, Pag 35R vband, spec twin, enormous amount of go fast
      '03 GTI: Gutted, Parted & Transplanted
      '04 F250 6.0: 72mm turbo, 60 psi stupid fast for 8k lbs, sold to ejg3855
      '13 F150 Ecoboost: Ordered, Rec'd, Triple Black, Tow Truck for other Vehicles.

    3. 11-01-2007 04:24 PM #3
      never heard of that "trick". Anyone care to shed some light on that ?

    4. 11-06-2007 02:34 PM #4
      I heard that if you have low compression in a cylinder, then the method of putting some oil through the spark plug hole will allow the compression psi to be higher (the oil being a gap filler) as an indicator of bad rings. It doesn't matter what grade oil (same as what your using is probably best) but the amount you put in I'm not sure about.

    5. Member 20thAEGti1009's Avatar
      Join Date
      Jan 27th, 2005
      Location
      Martinsburg, WV
      Posts
      949
      Vehicles
      2003 VW GTi (Daily) 20th Anniverary GTi 1984 GTi (Project) 2004 Chevy 3500 Crew Cab DRW (Tow Rig)
      11-06-2007 06:10 PM #5
      just use a cap full of oil.. and that trick works wonders for sealing worn ring
      Force Fed Engineering
      Best Turbo Kits around.

      1984 GTi Big Turbo 20v swap in progress.

    6. 11-06-2007 08:24 PM #6
      Hopefully this will be a sticky

    7. Member matimus's Avatar
      Join Date
      Nov 10th, 2003
      Location
      Long Beach, CA
      Posts
      972
      Vehicles
      01 A4 Avant
      11-06-2007 10:35 PM #7
      Great info! Thanks

      bump to make a sticky!


    8. Member crazyass713's Avatar
      Join Date
      Dec 27th, 2006
      Posts
      5,348
      Vehicles
      01 Golf mid-enine 2.7T Twincharged, 04 B6 USP 2.0T built
      11-07-2007 12:21 PM #8
      Quote, originally posted by Tongster »
      I heard that if you have low compression in a cylinder, then the method of putting some oil through the spark plug hole will allow the compression psi to be higher (the oil being a gap filler) as an indicator of bad rings. It doesn't matter what grade oil (same as what your using is probably best) but the amount you put in I'm not sure about.

      a cap full of oil in the spark plug hole will suffice for amount... if your compression jumps more than 10psi during a wet compression test, i would be somewhat concerned

      2001 Golf mid-engine RWD Allroad 01E 2.7T TVS1320 BW S374 twincharged (long title, I know)

      2004 A4 Ultrasport 2.0T 3076R built to the hilt all the way around (daily sleeper status)

    9. Member Issam Abed's Avatar
      Join Date
      Feb 12th, 2004
      Location
      EVERYWHERE
      Posts
      13,365
      Vehicles
      91 Audi 80 2.0T
      11-07-2007 01:19 PM #9
      Quote, originally posted by theswoleguy »
      IE: teaspoon of oil in the cylinder to check for bad rings

      Emphasis on teaspoon.Growing up a job came into the work shop because the owner wanted to do his own compression testing,suffice to say he hydrolocked the motor.

    10. Member theswoleguy's Avatar
      Join Date
      Jan 24th, 2006
      Location
      Atlanta, GA
      Posts
      7,831
      Vehicles
      A few...
      11-07-2007 01:39 PM #10
      basically enough to just cover the top of the piston
      Project GTi-R:. '04 R32 Chassis w/ 1.8t transplant in the werks
      '01 Audi TTQ Roadster: QED motor, Pag 35R vband, spec twin, enormous amount of go fast
      '03 GTI: Gutted, Parted & Transplanted
      '04 F250 6.0: 72mm turbo, 60 psi stupid fast for 8k lbs, sold to ejg3855
      '13 F150 Ecoboost: Ordered, Rec'd, Triple Black, Tow Truck for other Vehicles.

    11. 11-07-2007 02:47 PM #11
      LOL, I guess that customer must have put a quart in each spark plug hole

    12. Member
      Join Date
      Aug 2nd, 2011
      Location
      Central FL
      Posts
      175
      Vehicles
      93 Corrado SLC- VRT. 350Z Turbo 500whp.
      08-03-2011 11:13 AM #12
      lol!

    13. 09-11-2011 06:14 PM #13
      If you have an AWD engine code unbolt the coils from the head and remove the vacuum reservoir (canister).. If you have an AWW or AWP engine code just remove the coils.
      Anyone know where the ATC engine code falls in the above statement? Remove the vacuum reservoir or not?

    Posting Permissions

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