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Author Topic: compression test results  (Read 944 times)

Offline ald1717

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compression test results
« on: June 18, 2022, 10:54:56 pm »
cars being given to my younger brother in a couple of weeks so i thought i would test compresion just incase there was a bad piston or ring somewhere being 16 years old and having 113000k on it,
i was suprised that all 4 cylinders were near identical at 175 psi , really didnt expect that, but what i did realise was that the spark plugs on cylinders 3 and 4 behind the pcv valve had what looked like a slight grayish colouring, is this from being the closest plugs to the pcv return line into the manifold?

Offline ROH ECHT

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Re: compression test results
« Reply #1 on: June 19, 2022, 12:46:58 am »
I doubt it is from the PCV tube connected near there. Mine (3 & 4) never appear different. This doesn't mean its rocker cover hasn't separated right near where the PCV-to-manifold tube connects. In guessing, if this were the case, it may dump more oil into the manifold. But is there much oil in the tube itself?
K04 PLAY...K04 turbo/S3 INJ. & FMIC/FORGE FMTC, TB hose, & WG actuator/GIAC's H.O. K04 & DSG TUNES/AWE DV/NEUSPEED P-FLO,TURBO OUTLET & TB pipe/AUTOTECH hpfp/BSH Eng.&Trans Mounts/H&R ARB's/Whiteline Performance springs & W.A.L.K./ECS stage-3 BBK/BILSTEIN B8's...ZOOM'DIS...GIAC K04 tune-2007 Volkswagen GTI: 12.823 @ 112.050 MPH__Voting for my Dragtimes link: http://www.dragtimes.com/Volkswagen-GTI-Timeslip-25700.html?r=1

Offline ald1717

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Re: compression test results
« Reply #2 on: June 19, 2022, 01:04:16 am »
hard to say there always seems to be a fair bit and i do get the occasional puff of smoke from the exhaust if ive been cruising for a while then com on boost but ive been told this is normal vapours burning and i do have a bigger down pipe and 200 cel,

Offline ROH ECHT

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Re: compression test results
« Reply #3 on: June 20, 2022, 05:26:24 pm »
hard to say there always seems to be a fair bit and i do get the occasional puff of smoke from the exhaust if ive been cruising for a while then com on boost but ive been told this is normal vapours burning and i do have a bigger down pipe and 200 cel,
Mine was rebuilt at 120k miles. When it first began to release a small puff, was right after lifting the throttle after putting it into boost. Then what it developed was; if I stopped after having it in boost, it would puff again when going back on throttle when rolling from a stop. Eventually it got to doing this more often and produced a more embarrassing cloud. Mine turned out to be worn valve guides, valve stem seals, and rings becoming stuck in the pistons of #3 and #4. In this you can see how much more oil was in the #3 and #4 combustion chambers:


K04 PLAY...K04 turbo/S3 INJ. & FMIC/FORGE FMTC, TB hose, & WG actuator/GIAC's H.O. K04 & DSG TUNES/AWE DV/NEUSPEED P-FLO,TURBO OUTLET & TB pipe/AUTOTECH hpfp/BSH Eng.&Trans Mounts/H&R ARB's/Whiteline Performance springs & W.A.L.K./ECS stage-3 BBK/BILSTEIN B8's...ZOOM'DIS...GIAC K04 tune-2007 Volkswagen GTI: 12.823 @ 112.050 MPH__Voting for my Dragtimes link: http://www.dragtimes.com/Volkswagen-GTI-Timeslip-25700.html?r=1