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compression--leak down question


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sounds like im gaskets.

do the carb cleaner only when the car is symptomatic

 

If you have not replaced them yet, after being on here for how long...

 

You should suspect that first.

305,600miles 5/2012 ej257 short block, 8/2011 installed VF52 turbo, @20.8psi, 280whp, 300ftlbs. (SOLD).  CHECK your oil, these cars use it.

 

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If you have not replaced them yet, after being on here for how long...

 

You should suspect that first.

 

Yeah, I know...But remember that I am on the other side of the pond right now without a garage, and readily available parts for my car. So it's a bit more difficult for me :(.

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  • 2 weeks later...

update: waiting for IM gaskets to be shipped to me with a new air filter. FINALLY found a shop that will do a compression / leak down tests next week.

 

FYI, got a misfire on #2 last week when fully warmed up while idling at a traffic light. This happened right after hitting a bit of boost in second. So now, got 2 misfires (2 and 4). First time on 2.

 

I am no longer driving the car in fear of destroying it, even though it still runs somewhat OK.

 

For now, thinking of checking OCV on driver side and clean it as well; plus do the carb cleaner test on IM gasket area. Never hurts.. Once I receive the gaskets, will install them, install new air filter, and clean MAF.

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Update:

1. new paper air filter installed

2. cleaned MAF

3. leak down test result: 10% leak on #4 through piston ring. Mechanic says it is within spec and is therefore OK. So he thinks that valves probably need adjustments :confused:.

4. Still getting misfire on #4. Has occurred either cold or warm, at idle, and even at higher rpm under load.

 

They did not do any compression test. Felt it was unnecessary.

 

What do you guys think of their diagnosis?

 

Reminder: I have new spark plugs, injector, and swapped coils.

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10% is cutting it close. Questionable. If you swapped injectors, coils, and plugs. that doesn't leave much left. the reason to do a leakdown is to determine the origin of the leak. they said themselves it was piston leaking(listening while the leak occurs with your ear to the oil fill cap), yet they're saying it could be a valve issue. well if they did the test correctly, they'd listen in the throttle body if it was leaking via the intake valves, and listen in the exhaust ports if it was an exhaust valve issue(after dropping the exh manifold). see what I'm saying?
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Yeah. I did specifically asked him if he did listen for air leaks at the exhaust, throttle body, and oil cap. The leak came from the oil cap.

He thought 10% is just fine. So he thought the issue comes from valves being out of specs. So I was like :confused:.

 

To his defense though, I did get a busted TB tensioner while driving 10000 miles ago. Car ran OK after the fix, so who knows.

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it's questionable. 10% is pretty close to the limit. Might as well do a compression test on that cyl to see what that leak percentage yields in psi during compression stroke.

 

That is exactly my plan. Next week, I'll get a compression test with another guy. That other guy also feels like re-making sure that ignition is in good working order. Soooo, more waiting and no driving :(

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awaiting for compression results as I write, suspense is killing me :mad:.

 

On another note, I'd like to bump the following troubleshooting steps I previously posted. Has anyone really tried this?

 

http://legacygt.com/forums/attachment.php?attachmentid=142006&d=1360796895

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I will be doing mine tomorrow... too bad you weren't closer we could have gone through all this sh*t together.. lol.. GLWDiag

 

Since its in the SM Im guessing it works to a certain extent, just doesn't pinpoint failure to actual cylinder location. Leakdown and compression will narrow it down, other than that this might be good enough for me..

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