Author Topic: replacing cracked exhaust manifold on a 2003 GTI (180bhp, KO3s, 6 speed)  (Read 2233 times)

Offline VAG_minion

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Hello all, just joined this forum as i've been struggling to find solid information on this.

My exhaust manifold has a crack about 2" long, car still runs ok but reluctant to drive around in it too much in case a piece breaks off all together. it seems to close up after it warms up as well but would still like to sort it.

first question is - is there a step by step guide online anywhere that could help me with this?
(dont have the money to fork out for a garage to do it. know my way around a car just never done a manifold with a turbo before)

secondly - would it be worth while replacing it with an up graded hi flow type exhaust?
(if so which brand, and are there any sealing/fitting issues with the gasket on 'hi flow' manifolds.

third - part numbers or recommended websites/manufacturers to purchase manifold.
(bearing in mind cost will be a deciding factor, local dealer quoted £330 for the manifold alone, i think i'd attempt welding it before spending that on it at the moment)

only had the car a week or so i originally thought the slight tell tale 'puff puff' noise when you switched it off was a leak in the flexi on the down pipe. but it was the b*****d manifold   :whistle:

engine code is AUQ. any help much appreciated.


Offline barrym381

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try find a second hand 1 if you don't fancy buying a new 1  :smiley: had to get mine from the dealer when mine went as most second hand 1s had cracks too

Offline VAG_minion

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cheers for your reply.
aye, i've been eyeing some up second hand. the serial number if im reading it right is 06A 253 033.
 i've seen one or two online advertised for different vehicles of different years and for AGU engine code but the advert says it wont fit my vehicle, but on inspecting the photos i can see the same serial number, it also looks identical to other ones that are advertised as fitting my car.
surely this serial number means the part is identical or could it have slight variations between years? any ideas about these 'hi flow' ones, cheers

Offline Dalo Harkin

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definitely just get a second hand one, surely you can find one on ebay or in the forums.

Its quite easy to do just VERY time consuming, all you need here in terms of what to do, I followed this when my K03s went
http://uk-mkivs.net/topic/17385-k03-k03s-turbo-diy-how-to-fitting-guide-mk4-golf/
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 Wazzzer

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You'll need new bolts and manifold nuts along with the relevant gaskets. It's not too bad to take just the manifold off, the main problem you'll have is the nuts/bolts being tight from years of heating up and cooling down. Plus gas will be your friend...

You'll have to drop the turbo down slightly to gain access to a couple of the bottom nuts on the manifold but you don't have to take the downpipe off to do this; just loosen the bolt to the support bracket that bolts to the back of the block. The fun bit is getting the nuts back on afterwards lol


1999 1.8T: R-Tech remap - 225bhp/256lb/ft : K03s : THS FMIC : THS PCR pipe : 2.5" stainless exhaust : THS FR3 Engine mounts : G60/VR6 clutch : Calibra Yellow injectors : VR6 MAF : Devils Own WMI : Forge 007p : Carbonio CAI : Leon Cupra R Brembos : FK AK Street coilovers : Votex skirts : Anniversary front : click ---> http://www.golfgtiforum.co.uk/index.php?topic=92175