MK5 Golf GTI

All Things Mk5 => How to Guides / Troubleshooting => Topic started by: Markyed30 on March 30, 2014, 07:17:05 pm

Title: boost leak at intercooler
Post by: Markyed30 on March 30, 2014, 07:17:05 pm
After iv went apr stage 1+ after 20 psi I thought what I could hear was the wastegate opening and closing and my boost guage flickers like mad, iv noticed I'm leaking oil from passenger side intercooler there quite a bit on the drive and what iv been hearing is most likely a boost leak under load and been having issues with missfires.
Where do I go from here I'll take the bumper off do I change the jubilee clips or pipes ect??
Title: Re: boost leak at intercooler
Post by: JMP on March 30, 2014, 07:56:57 pm
Lift it up and remove the bottom plastic tray. I would first just check where its leaking, if its a joint, remove and clean the pipes where they make contact. You should check the pipes for damage where you see its dripping. Ic piping is quite easily accessable from under, no need to take bumper off if its problem with piping. If i remember correctly, the basic mkv gti had no jubilee clips so you might have to replace part of the piping if the connector clips fail. But you should just take a look at whats causing the problem. It should be easy to see because of the oil..
Title: Re: boost leak at intercooler
Post by: Markyed30 on March 30, 2014, 08:55:50 pm
Ok thanks after searching I'll order 2 new o rings and change them while I'm there thanks
Title: Re: boost leak at intercooler
Post by: Tfsi_Mike on March 30, 2014, 09:25:28 pm

Looking at the front of the car, my cooler pipe on the left has had the Oring fail once causinge to lose boost. Oil seeped from the coupling. Was only pennies to replace.

Hope you get to the bottom of it
Title: Re: boost leak at intercooler
Post by: Markyed30 on April 05, 2014, 08:11:00 pm
Amazing how a £5 gasket can solve a problem  :signLOL:

(https://www.mk5golfgti.co.uk/forum/proxy.php?request=http%3A%2F%2Fs15.postimg.org%2Frq7ren16j%2FDSC_0526.jpg&hash=59c3083f0f476ccf5ed83f7d0155c40127cebef6)
You can see the gasket had stretched and fouled up on bottom
(https://www.mk5golfgti.co.uk/forum/proxy.php?request=http%3A%2F%2Fs3.postimg.org%2F8vcssm583%2FIMG_20140405_WA0004.jpg&hash=5153d3fb6508296a341df6d35a372323a1096214)

New gasket
Title: Re: boost leak at intercooler
Post by: Markyed30 on April 05, 2014, 08:15:58 pm
3c0145117H is the new part number for gasket  :drinking:
Title: Re: boost leak at intercooler
Post by: GrayMK5GTI on April 06, 2014, 10:40:56 am
3c0145117H is the new part number for gasket  :drinking:

Thanks for this  :drinking:

I can see mine leaking slightly here. Glad it's a cheap fix  :smiley:
Title: Re: boost leak at intercooler
Post by: ginge 0116 on April 16, 2014, 09:59:24 pm
Hi guys I've noticed I've got the same issue with mine. Was just wondering what tools are required and if a novice would be able to change the part. Or would it be best if I take it to a garage cheers sam
Title: Re: boost leak at intercooler
Post by: Markyed30 on April 16, 2014, 10:36:47 pm
Jack up car and use a tx25 bit remove 6 or 8 screws then pull of undertray and you can pull clip off with ur hand to release pipe then fit new o ring and re clip took me 5 min  :happy2:
Title: Re: boost leak at intercooler
Post by: doylebros on July 10, 2014, 09:41:18 pm
In case this helps anyone the pipe has two different seals at either connection point

I done the following inter cooler seals
1 x 3C0 145 117 H
1 x 3C0 145 117 F

£11.47 inc vat,
Title: Re: boost leak at intercooler
Post by: 18Edition30 on August 03, 2014, 09:45:19 pm
In case this helps anyone the pipe has two different seals at either connection point

I done the following inter cooler seals
1 x 3C0 145 117 H
1 x 3C0 145 117 F

£11.47 inc vat,

Is this just for the drivers side pipe? Which has o rings both ends?

Where as I'm sure the passenger side pipe only has o ring one end, as the other end is jubilee clipped on?

I'm looking for the o ring for the passenger side connection!
Title: Re: boost leak at intercooler
Post by: bacillus on August 03, 2014, 10:02:31 pm
I'm looking for the o ring for the passenger side connection!

You need a 3C0 145 117 F o-ring

Title: Re: boost leak at intercooler
Post by: Markyed30 on August 04, 2014, 12:20:58 am
3c0145117H
Was the oring I ordered and fitted to the passenger side and was the updated number to the one I had supplied to dealer !!
Title: Re: boost leak at intercooler
Post by: Broomy on September 18, 2014, 10:39:48 pm
Got this problem myself so need to order up some o-rings, are they both the same part number? Or is it F for passenger / H for driver side I'm confused lol
Title: Re: boost leak at intercooler
Post by: GTIEagles on June 30, 2015, 11:45:02 am
Thread resurrection!

I noticed yesterday when I got under the car that the intercooler pipe is weeping oil slightly on the drivers side, I guess that replacing the o-rings should definately fix the problem?
Title: Re: boost leak at intercooler
Post by: GrayMK5GTI on June 30, 2015, 12:51:28 pm
Thread resurrection!

I noticed yesterday when I got under the car that the intercooler pipe is weeping oil slightly on the drivers side, I guess that replacing the o-rings should definately fix the problem?

thats right, unless pipe has split  :happy2:
Title: Re: boost leak at intercooler
Post by: GTIEagles on June 30, 2015, 01:18:23 pm
Great, I'll get those ordered  :happy2: