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Old 08-01-2012, 01:28 AM   #1
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Default compression test results HEEELLPPPP!!

when doing compression test i got the following resuslts
(from front of car to back)
1st- spark plug came at drenched in oil and psi of 90
2nd- spark plug also drenched in oil and psi of 100
3rd- spark plug came out with no oil and psi of 100
4th-spark plug came out drenched in oil and psi of 110

the oil shows no signs reaching my cylinder just visual of it being in my spark plugs...i think it might be the valve seals??? any ideas?

p.s i need a hug
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Old 08-01-2012, 09:56 AM   #2
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ideas? tear it apart and rebuild
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Old 08-01-2012, 10:03 AM   #3
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what promted you to do the test?


how EXACTLY did you do it (the test that is)? make sure to leave out important details.
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Old 08-01-2012, 12:18 PM   #4
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If your car still runs, those results are inaccurate.
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Old 08-01-2012, 01:44 PM   #5
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Combine his two threads on this and there still isn't enough info to make one thread.
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Old 08-01-2012, 01:58 PM   #6
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Valve cover gasket? Was there oil pooled in the spark plug hole before you pulled the plugs?
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Old 08-01-2012, 02:02 PM   #7
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Did you have the throttle held wide open? Did you do 6 cranks? If so its time to turn that compression tester into a leak down tester to figure out whats broken.
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Old 08-01-2012, 02:51 PM   #8
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Quote:
Originally Posted by Leafy View Post
Did you have the throttle held wide open? Did you do 6 cranks? If so its time to turn that compression tester into a leak down tester to figure out whats broken.
I second this. do a leak down. If air blows out your IM or Exhaust it's your head. if you get bubblies in your radiator it's your head gasket, if you get air coming out of your dipstick hole even though you may be used to that it's blowby. You need to go into the bottom and dig around. yes i know also something you are accustomed to.

If it's leaking out of intake or exhaust ports i'm guessing you aren't going to rebuild or diagnose the head so take it to a shop and let them diagnose and then rebuild or give it a valve job.
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Old 08-01-2012, 03:06 PM   #9
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Quote:
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If your car still runs, those results are inaccurate.
I've seen worse numbers on a turbo miata still making power.

Ever played the game "spy hunter?" It was similar...
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Old 08-01-2012, 07:04 PM   #10
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my first motor started with

#1 - 85
#2 - 110
#3 - 115
#4 - 80

lol my breather valve looked like a chimney.
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Old 08-01-2012, 07:15 PM   #11
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And I thought I was doing bad with 130-140 on all cylinders that jumps up to 175 when oil is added. Stupid old people who broke in this engine, I bet it has had low comp for the entire 80k miles of its life.
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Old 08-02-2012, 12:41 AM   #12
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lets see a pic of the plugs drenched in oil
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Old 08-02-2012, 01:40 PM   #13
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What gauge did you use? The numbers are still pretty even accross the cylinders and it might be the gauge reading low.
Does it feel like that car has no power? If your compression ratio was realy that low I would imagine that it would feel down on power and more than likely burn a good bit of oil. +1 on the leakdown test.
Is the ceramic (external) part of the plug coated in oil or is it the tip (internal)? If only the ceramic part is covered in oil and the tip of the plug is not covered in oil or thick carbon it is more than likely just the valve cover gasket leaking.

Good luck.
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Old 08-02-2012, 03:16 PM   #14
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Quote:
Originally Posted by hornetball View Post
Valve cover gasket? Was there oil pooled in the spark plug hole before you pulled the plugs?
That was my first thought. Scares the crap out of you the first time you see oil all over the plug.
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Old 08-02-2012, 03:33 PM   #15
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Luke Skywalker, Y U NO REPLY?
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Old 08-02-2012, 10:12 PM   #16
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thanks everyone for all the help and advice, turns out the gauge was reading low..did compression test again took off spark plugs, cranked six times and BAAAAM
#1-200 #2-190 #3-190 #4-200

most of you guys were right on point with me just needing to replace the valve cover gasket..

as far as the overheating, my fan isnt turning on which i also fixed

thanks again everyone and sorry for the late reply
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Old 08-02-2012, 11:46 PM   #17
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God D!!! I wish I had those compression numbers!!!
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Old 08-02-2012, 11:48 PM   #18
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No kidding. Stock is only supposed to be a bit over 180.
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Old 08-02-2012, 11:50 PM   #19
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I bet if I had numbers like that, I'd see 240whp, not 225.
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Old 08-02-2012, 11:53 PM   #20
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Possibly. And remember compression test numbers dont really have anything to do with compression ratio its the sealing of the combustion chamber that has the biggest impact. Almost all car's I've seen ranging from 9:1 to 11:1 factory compression spec 180 psi as being normal.
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