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Low Compression on 2 Cylinders, May have Blown Rings....

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Old Mar 22, 2008 | 06:00 PM
  #21  
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Take your plenum off and see if there is oil in it.Even stock Vq's eat a little oil, what year is your car.
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Old Mar 22, 2008 | 06:08 PM
  #22  
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2005, kind of like it says in my .sig.

Also, I had already mentioned there was oil in the intake, thats what started this whole thing.
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Old Mar 23, 2008 | 11:23 AM
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My bad did not even think to look.Well the only thing really left to do is a leakdown test.When you do this, if you do. It will tell you instantly if there is a leak in the system.If you hear air excaping the intake or exhaust side you know you have a valve problem.If you hear it excaping the pcv system there is blow-by, most likly a ring problem.Post results for further diagnosis.

If the smoke is tolerable with you drive it tell it breaks and hope you don't throw a rod through the block or destroy your heads cause of oil contamination(metal).

Either way if you end up disasmebling the block.Yes it would be worth while for you to slap some new bearing, rods, pistons, and rings in. 14PSI with thoughs 530's is pretty nice.

Originally Posted by Dave 90TT
2005, kind of like it says in my .sig.

Also, I had already mentioned there was oil in the intake, thats what started this whole thing.
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Old Mar 23, 2008 | 05:22 PM
  #24  
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Yeah, the thought of running 14 PSI on a built block is quitte nice!
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Old Mar 23, 2008 | 07:24 PM
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Old Mar 23, 2008 | 07:26 PM
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Im actually in your situation right now. My rings are shot and i have oil on my 3rd and 6th piston. My cars knocking bad though. I dont know if yours is but i think my rings might have broken off and the piston is slapping around.

anyways, MY PLANS are to pull the motor and buy this kit right here.

http://www.importpartspro.com/st1blon.html

I say, you gotta pull your pistons off anyways, why not build it. if you put oem internals again, you will run into the same problem and waste more time and money.
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Old Mar 23, 2008 | 08:18 PM
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Those compression numbers look better than I would have expected after that quick test at the track. It sounds like a leak down test will be more conclusive. Hopefuly you can get this reolved quickly and get that beast back on the track -- or get the build started ASAP!
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Old Mar 24, 2008 | 12:36 AM
  #28  
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Yeah, I think the motor is doing fine for now. Still not sure how all the oil got in the intake.

Anyways, if I do end up having to pull the pistons, I will be building it, I've definitely decided that.

350 Rookie, I hope things work out for you!
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Old Mar 24, 2008 | 09:30 AM
  #29  
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Originally Posted by Dave 90TT

350 Rookie, I hope things work out for you!
thanx and actually here are my numbers
1. 155
2. 163
3. 120 (alert)
4. 165
5. 155
6. 170
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Old Mar 24, 2008 | 09:37 AM
  #30  
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Yeah, that 120 on cylinder 3 is bad, as I'm sure you know.

Edit: were those wet or dry numbers? If they were dry, you should try wet on cylinder 3 and see if it goes up. If it does, bad rings.
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Old Mar 24, 2008 | 09:46 AM
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Originally Posted by Dave 90TT
Yeah, that 120 on cylinder 3 is bad, as I'm sure you know.

Edit: were those wet or dry numbers? If they were dry, you should try wet on cylinder 3 and see if it goes up. If it does, bad rings.
how much oil do i put on the cylinder though.

Last edited by 350 Rookie; Mar 24, 2008 at 09:50 AM.
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Old Mar 24, 2008 | 09:54 AM
  #32  
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2 tablespoons shoud do it. Got to crank it a couple of times to ensure that the rings get coated.
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