Author Topic: Finding a boost leak.  (Read 2046 times)

Offline Pez

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Finding a boost leak.
« on: 13 December 2012, 16:03 »
Just been to look at a 1.8T that I'm thinking about buying, the owner says he thinks it might have a boost leak. What's the best way to find out where it's coming from and is it just the hoses that are likely to be the cause?
Thanks in advance -Pez

Offline Dalo Harkin

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Re: Finding a boost leak.
« Reply #1 on: 13 December 2012, 17:03 »
boost leaks leak oil - start there.

Yes all the pipes under the plate on the inlet are most common and then the PCV system  :wink:
ARZ K03s, Oettinger Side Skirts, R32 front, Carbon stage 2, Forge 007p (yellow spring), Forge Actuator (yellow spring), Pipercross panel filter with DSG parts, N249 and N112 deleted, SAI deleted, Carbon canister deleted, Rear wiper deleted, Long Life turbo back custom exhaust with 200 cell sports cat, VR6/G60 clutch kit, Creation Motorsport TIP, Catch can, 'Wellycooler', K04 charge pipe, S3 ported inlet manifold - looks pretty standard on the outside though :)

Offline Pez

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Re: Finding a boost leak.
« Reply #2 on: 13 December 2012, 20:26 »
boost leaks leak oil - start there.

Yes all the pipes under the plate on the inlet are most common and then the PCV system  :wink:
Cheers mate.

Offline BarryMKIV

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Re: Finding a boost leak.
« Reply #3 on: 13 December 2012, 22:22 »
Smoke test.

25th Anniversary GTI 1.8T No. 0441

Offline jamie1989

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Re: Finding a boost leak.
« Reply #4 on: 14 December 2012, 09:10 »
1.8t's are pretty easy tbf.

If you cant afford a smoke test I would start from the top of the turbo and follow it all the way down to the intercooler, then from the intercooler to inlet. Even if it means removing all these pipes and check for obvious splits.

If you have found nothing remove the engine covers and check under the inlet manifold youl find a few pipes connected to it, these are under vaccum and perish over time. If they are perished time to invest in new pipes or perfect oppertunity to get a catch can installation.

Goodluck
1.6-1.8t AGU K03s, Forge actuator, Forge 007p, turbo back exhuast, Ths front mount, Catch can, 5 piece silicone boost pipes and creation sports tip. Stage 2 atm 232bhp 270lbs. Waiting for custom mapping :-)

Offline GTi_James

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Re: Finding a boost leak.
« Reply #5 on: 14 December 2012, 09:16 »
welcome and i hope you have been saving all your pennies from the paper round!  :whistle:  :laugh:

and first thing i'd do is replace the PVC with a catch can  :wink:


Mk4 Golf 1.8t AUM, Wintersports Addition. PiperX panel filter, 008p Forge DV, Toyosports DP 3", Miltek Anni Style CatBack non resonated, APR Sport CAT 200Cell, Catch Can RS4 Reps 18s, OEM R32 front and OEM

Offline tshirt2k

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Re: Finding a boost leak.
« Reply #6 on: 14 December 2012, 09:35 »
Just checking pipes won't find you leaks. You need a smoke test or make a boost leak tester using some plumbing bits and a compressor. Pressurise the system and you'll hear the leaks.


Mk3 ABF 16VT Megasquirt V3

Tshirt knows........ How to diagnose

Offline jamie1989

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Re: Finding a boost leak.
« Reply #7 on: 14 December 2012, 10:17 »
Iv found plenty of leaks before.
Never in my life used a smoke test either.

Using the method above will 9/10 find your leak.

My very best mod was a boost guage this way I always knew if I had a leak. I would recomend every 1.8t have them as they are getting old now and all the boost pipes and vaccum pipes are bound to perished by now.
1.6-1.8t AGU K03s, Forge actuator, Forge 007p, turbo back exhuast, Ths front mount, Catch can, 5 piece silicone boost pipes and creation sports tip. Stage 2 atm 232bhp 270lbs. Waiting for custom mapping :-)

Offline Dalo Harkin

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Re: Finding a boost leak.
« Reply #8 on: 14 December 2012, 12:53 »
Just checking pipes won't find you leaks.

I don't have any and I dont have a smoke tester  :tongue:
ARZ K03s, Oettinger Side Skirts, R32 front, Carbon stage 2, Forge 007p (yellow spring), Forge Actuator (yellow spring), Pipercross panel filter with DSG parts, N249 and N112 deleted, SAI deleted, Carbon canister deleted, Rear wiper deleted, Long Life turbo back custom exhaust with 200 cell sports cat, VR6/G60 clutch kit, Creation Motorsport TIP, Catch can, 'Wellycooler', K04 charge pipe, S3 ported inlet manifold - looks pretty standard on the outside though :)

Offline jamie1989

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Re: Finding a boost leak.
« Reply #9 on: 14 December 2012, 13:00 »
 :grin:
1.6-1.8t AGU K03s, Forge actuator, Forge 007p, turbo back exhuast, Ths front mount, Catch can, 5 piece silicone boost pipes and creation sports tip. Stage 2 atm 232bhp 270lbs. Waiting for custom mapping :-)