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what do these say to you? compression numbers added

Started by night_s12 · Feb 17, 2013 · 13postsSMF 2010–26

night_s12Feb 17, 2013, 1:41 pm · #1

Left to right cylinder #
2, 4, 6.   I know cylinder 4 seems to have a coolant leak near it.
 http://i1295.photobucket.com/albums/b630/night_s12/IMG_20130217_132758_zps7b2649c0.jpg
1, 3, 5
 http://i1295.photobucket.com/albums/b630/night_s12/IMG_20130217_132829_zpsdd5d44a8.jpg
I'm about to do a compression test but I'm pretty sure those say unburnt fuel

Compression #'s
 Cylinder 1 180
Cylinder 3 160
Cylinder 5 170
Cylinder 2 160
Cylinder 4 150
Cylinder 6 155

WonderingravenFeb 17, 2013, 2:08 pm · #2

Wished I knew more. I will though one day.

night_s12Feb 17, 2013, 2:42 pm · #3

Thanks anyway man. 1 day I will too

Colonel GustardFeb 17, 2013, 3:12 pm · #4

Compression is pretty solid all the way accross, numbers are close and thats a good sign.
Post Merge


The difference from the highest and lowest number should be about 5%-10%
night_s12Feb 17, 2013, 3:17 pm · #5

Why thank you Gus. That's awesome to know. But what about those plugs?

Colonel GustardFeb 17, 2013, 3:19 pm · #6

Pics are too blurry, can't see them too well

night_s12Feb 17, 2013, 3:27 pm · #7

I know my phone blows but you can see where there super black and where there all white

Ju_S12_TurboFeb 18, 2013, 2:39 am · #8

The plugs look hot and lean (imo) from the pics. If it were me i'd just do a leak down test.

night_s12Feb 18, 2013, 3:42 am · #9

How does one do that?

BoostedVGFeb 18, 2013, 2:30 pm · #10

180 psi is normal and what you want to see. Anything within 10% of that is exceptable. So if you do the math you have 2 cylinders that are not making the grade. From the looks of of your plugs you may have some fuel injector issues. If your cylinders are being washed with too much fuel you compression will be low. Try dumping some oil in the cylinders and do another compression test.

night_s12Feb 18, 2013, 2:45 pm · #11

Those would be what cylinders 4 and 6? How much oil like half a cap?
Post Merge


And if the oil brings the psi up what would that mean? Bad rings or something?
BoostedVGFeb 20, 2013, 12:54 pm · #12

yeah 4 and 6 and at least a 1/2 cap.  I'm assuming you have washed or bad rings. If the oil brings back the compression I might try another set of injectors.

night_s12Feb 20, 2013, 3:30 pm · #13

Alright cool thanks.