1. Join the Community!

    DSMtuners is a massive archive of DSM information - but more importantly, it's a COMMUNITY! Join in and participate with other DSMers, and invite all of your DSM friends to make this place their home. Chat with others, create a build thread, post questions and answers. Get involved! Logging in will also remove many of the advertisements, along with this notice. ;)

2G Compression test

Posted by Ces4rDSM, Aug 14, 2019

Please Support Fuel Injector Clinic
Please Support ExtremePSI
  1. Ces4rDSM

    Ces4rDSM Proven Member

    102
    5
    Joined Feb 2, 2019
    watsonville, California
    I've been trying to get my compression numbers per cylinder and it looks like all cylinders read 60 psi. Please help I'm not sure what I'm doing wrong. I unplugged one spark plug at a time, spark plug wires are off and power is disconnected. I opened the throttle as much as I could with a screwdriver or yet still same results. Can it be the compression tester itself that I borrowed from Autozone ?
     

    Street Build 121  1

    1997 Mitsubishi Eclipse Spyder GST
    fwd · manual · 2G DSM
    Loading...
  2. BLACK'98DSM

    BLACK'98DSM Proven Member

    328
    84
    Joined Feb 9, 2019
    Hoover, Alabama
    60 psi is absolutely wack. Are you sure you have the tester screwed all the way in tightly? And are you trying to crank the engine or just manually rotating it?

    And by the way you can buy cheap testers on Ebay and Amazon if you want to and don't trust Autozone's.

    Amazon

    Ebay
     

    Street Build 963  8

    1998 Mitsubishi Eclipse N/T
    fwd · manual · 2G DSM

    114  6

    2009 Troy Bilt Bronco
    rwd · automatic · Misc Vehicles

    192  1

    2012 Murray Explorer Dune
    rwd · automatic · Misc Vehicles
    Loading...
  3. Ces4rDSM

    Ces4rDSM Proven Member

    102
    5
    Joined Feb 2, 2019
    watsonville, California
    Yes as tight as I could I screwed them in. I opened the throttle with a screwdriver as well.
     

    Street Build 121  1

    1997 Mitsubishi Eclipse Spyder GST
    fwd · manual · 2G DSM
    Loading...
  4. Ces4rDSM

    Ces4rDSM Proven Member

    102
    5
    Joined Feb 2, 2019
    watsonville, California
    I turned over the keys and even pressed on accelerator.
     

    Street Build 121  1

    1997 Mitsubishi Eclipse Spyder GST
    fwd · manual · 2G DSM
    Loading...
  5. luv2rallye

    luv2rallye DSM Wiseman

    7,448
    505
    Joined Jun 7, 2003
    Minneapolis, Minnesota
    Probably bad tester or a leak in the tester hose connection. BTW it's easier and will spin faster if you just leave all spark plugs removed.
     
    Last edited: Aug 14, 2019

    2K  0

    1999 Mitsubishi Eclipse GST
    14.200 @ 95.000 · 2G DSM
    Loading...
    BLACK'98DSM likes this.
  6. Ces4rDSM

    Ces4rDSM Proven Member

    102
    5
    Joined Feb 2, 2019
    watsonville, California
    Yea the tester hose connected by the psi gauge was like magnet or pull to remove type of thing so probably that. I only did one spark plug at time, thought it would read more accurate ‍♂️ Anyways thank you all for input I will try a different compression tester.
     

    Street Build 121  1

    1997 Mitsubishi Eclipse Spyder GST
    fwd · manual · 2G DSM
    Loading...
  7. Jay_gst97

    Jay_gst97 Probationary Member

    22
    6
    Joined Aug 15, 2019
    Ellenville, New York
    U should unhook the plug to your coil pack and pull ur fuel pump relay or fuse or w.e u don't want fuel pumping in there while your doing it and don't need to be accidentally shocked by a wire or something if u haven't done so already but sounds like the tester may be bad I know my tester has a big oring at the end of the threads so if it is missing compression may blow past the tool
     

    Street Build 109  1

    1997 Mitsubishi Eclipse Spyder GST
    fwd · manual · 2G DSM
    Loading...
  8. Ces4rDSM

    Ces4rDSM Proven Member

    102
    5
    Joined Feb 2, 2019
    watsonville, California
    I thought the tester would've been ok since it looked new I'm guessing it isn't working accuraty. I removed the spark plug connection although the fuel pump relay or fuse was still intact. I couldn't find it didn't think itd be a big issue unless I tried starting it too much .
     

    Street Build 121  1

    1997 Mitsubishi Eclipse Spyder GST
    fwd · manual · 2G DSM
    Loading...
  9. Jay_gst97

    Jay_gst97 Probationary Member

    22
    6
    Joined Aug 15, 2019
    Ellenville, New York
    I believe the fuel pump relay is behind the kick panel on the pass side below the radio there's 2 side by side I could be wrong if u search on here im sure u can find it
     

    Street Build 109  1

    1997 Mitsubishi Eclipse Spyder GST
    fwd · manual · 2G DSM
    Loading...
  10. Ces4rDSM

    Ces4rDSM Proven Member

    102
    5
    Joined Feb 2, 2019
    watsonville, California
    Oooo that's where it is. I was checking everywhere under the hood :beatentodeath: will check when I get to my car soon. Thank you for the input, if not I'll be back on here.
     

    Street Build 121  1

    1997 Mitsubishi Eclipse Spyder GST
    fwd · manual · 2G DSM
    Loading...
    Jay_gst97 likes this.
  11. stillrunning

    stillrunning Proven Member

    96
    43
    Joined Oct 10, 2013
    brandon, Florida
    You don't need to mess with the fuel at all, when you push the throttle wide open during start the injectors are off for flood clearing.
    You want to have all the spark plugs removed
    Install the pressure tester so that oring seals if it uses an oring, doesn't have to be really tight
    Push the throttle pedal to the floor and turn the ignition to start
    Let it spin for a little and the gauge should hold peak pressure for the cylinder being checked
     

    Street Build 375  3

    1997 Mitsubishi Eclipse Spyder GST
    fwd · manual · 2G DSM
    Loading...
    Jay_gst97 likes this.
  12. Ces4rDSM

    Ces4rDSM Proven Member

    102
    5
    Joined Feb 2, 2019
    watsonville, California
    Ohh ok I felt like there would be something integrated in the cars system that would make it ok to step on the throttle and not have worries about the fuel. I did as you're sayi but the most it would peak at was 75 psi and would go down to 60.
     

    Street Build 121  1

    1997 Mitsubishi Eclipse Spyder GST
    fwd · manual · 2G DSM
    Loading...
  13. Jay_gst97

    Jay_gst97 Probationary Member

    22
    6
    Joined Aug 15, 2019
    Ellenville, New York
    Yea I forgot about wot on cranking. but that doesn't really sound good I hope for your sake it is the tool not working properly good luck bro
     

    Street Build 109  1

    1997 Mitsubishi Eclipse Spyder GST
    fwd · manual · 2G DSM
    Loading...
  14. Ces4rDSM

    Ces4rDSM Proven Member

    102
    5
    Joined Feb 2, 2019
    watsonville, California
    Yea I hope so too man, it shouldn't be correct if my motor runs ok except for sounds coming from it. Because 60 psi is inoperable conditions in the pistons if I'm correct. Anyways thank you all for your input, I wish the best with our killer dsms :hellyeah:
     

    Street Build 121  1

    1997 Mitsubishi Eclipse Spyder GST
    fwd · manual · 2G DSM
    Loading...
    Jay_gst97 likes this.
  15. stillrunning

    stillrunning Proven Member

    96
    43
    Joined Oct 10, 2013
    brandon, Florida
    I'm guessing something weird is happening if all you get it 75-60 across the board with a "good/normal" running engine.
    Did you let it spin over long enough, it takes a couple cycles per cylinder.
    You'll normally see the gauge move upwards after each cylinder cycle before peaking out/stop gaining.
     

    Street Build 375  3

    1997 Mitsubishi Eclipse Spyder GST
    fwd · manual · 2G DSM
    Loading...
  16. Ces4rDSM

    Ces4rDSM Proven Member

    102
    5
    Joined Feb 2, 2019
    watsonville, California
    I tried letting it do its thing for a couple seconds before releasing the key in the ignition and trying it again. The psi measurement reads a peak high 70 or 80 then gradually goes to 60 psi or so. Hoping it's a tool malfunction :confused: damn autozone, I hope the torque wrench I borrowed isn't wrong too.
     

    Street Build 121  1

    1997 Mitsubishi Eclipse Spyder GST
    fwd · manual · 2G DSM
    Loading...
  17. Jay_gst97

    Jay_gst97 Probationary Member

    22
    6
    Joined Aug 15, 2019
    Ellenville, New York
    U can always try alittle putting alittle oil in the cylinder retest it and see if the compression goes up alittle bit could be a sign of bad rings or something
     

    Street Build 109  1

    1997 Mitsubishi Eclipse Spyder GST
    fwd · manual · 2G DSM
    Loading...
  18. pauleyman

    pauleyman DSM Wiseman

    5,085
    963
    Joined Nov 19, 2011
    oklahoma city, Oklahoma
    If the tester drop pressure it's go get another one
     

    Street Build 2K  1

    1997 Eagle Talon TSi AWD
    awd · manual · 2G DSM
    Loading...
    BLACK'98DSM likes this.
  19. pauleyman

    pauleyman DSM Wiseman

    5,085
    963
    Joined Nov 19, 2011
    oklahoma city, Oklahoma
    Order. You didnt install correctly.
     

    Street Build 2K  1

    1997 Eagle Talon TSi AWD
    awd · manual · 2G DSM
    Loading...
  20. pauleyman

    pauleyman DSM Wiseman

    5,085
    963
    Joined Nov 19, 2011
    oklahoma city, Oklahoma
    Scratch that. The tester has a check valve. Whatever it reads it holds. If you watch it bleed down it's bad.
     

    Street Build 2K  1

    1997 Eagle Talon TSi AWD
    awd · manual · 2G DSM
    Loading...
    BLACK'98DSM likes this.
  21. BLACK'98DSM

    BLACK'98DSM Proven Member

    328
    84
    Joined Feb 9, 2019
    Hoover, Alabama
    Yes, it sounds like the tester isn't properly holding the pressure value as it should.
     

    Street Build 963  8

    1998 Mitsubishi Eclipse N/T
    fwd · manual · 2G DSM

    114  6

    2009 Troy Bilt Bronco
    rwd · automatic · Misc Vehicles

    192  1

    2012 Murray Explorer Dune
    rwd · automatic · Misc Vehicles
    Loading...
  22. pauleyman

    pauleyman DSM Wiseman

    5,085
    963
    Joined Nov 19, 2011
    oklahoma city, Oklahoma
    Dang I need to proofread. Lots of typos.
    I am saying tester is bad. If pressure drops after test is complete that's wrong. Tester should hold until user releases it.
     

    Street Build 2K  1

    1997 Eagle Talon TSi AWD
    awd · manual · 2G DSM
    Loading...
    BLACK'98DSM likes this.
  23. Ces4rDSM

    Ces4rDSM Proven Member

    102
    5
    Joined Feb 2, 2019
    watsonville, California
    Ohh no wonder it did have a side button which I'm guessing is to release the pressure.
     

    Street Build 121  1

    1997 Mitsubishi Eclipse Spyder GST
    fwd · manual · 2G DSM
    Loading...
  24. BLACK'98DSM

    BLACK'98DSM Proven Member

    328
    84
    Joined Feb 9, 2019
    Hoover, Alabama
    Yes, that's how they work, along with tire pressure gauges.
     

    Street Build 963  8

    1998 Mitsubishi Eclipse N/T
    fwd · manual · 2G DSM

    114  6

    2009 Troy Bilt Bronco
    rwd · automatic · Misc Vehicles

    192  1

    2012 Murray Explorer Dune
    rwd · automatic · Misc Vehicles
    Loading...
  25. Ces4rDSM

    Ces4rDSM Proven Member

    102
    5
    Joined Feb 2, 2019
    watsonville, California
    Nice to know ! :rocks:
     

    Street Build 121  1

    1997 Mitsubishi Eclipse Spyder GST
    fwd · manual · 2G DSM
    Loading...

Share This Page

Support Vendors who Support the DSM Community
Archer Fabrication ECM Tuning ExtremePSI Feal Suspension Fuel Injector Clinic Jacks Transmissions JNZ Tuning Kiggly Racing Morrison Fabrications OHM Racing RockAuto SouthBay Fuel Injectors STM Tuned VR Speed Factory WheelWell.com White Shed Speed