Boost Leak BEW TDI with my fix

speedy223

Veteran Member
Joined
Apr 8, 2015
Location
east texas
TDI
alh tdi new beetle 98, alh jetta 01, bew golf 04 all 5spds
this may be old hat for lots of you but in case it helps anyone i thought i would post it.

have an 04 Golf 5spd TDI that is a daily driver. been doing great but out of the blue it developed a weird issue where it would lose power with no code initially then finally an EGR code. not limp mode, just lose lots of get up and go.

changed fuel filter and all that good stuff wasn't fuel related. no smoke either.

i temp solved it by unplugging the EGR motor and it power would be fine.drove it for several weeks as i have other project in the shop and really wasn't planning on working on this one and it did great.


then it started squealing sort of like a harsh shrill sound on acceleration. No limp mode, no codes besides the one it already had for EGR plug being pulled and really ran fine. Noise would be present at about 7.5 psi boost or higher, go away as soon as i let off gas and coast.


i thought it might be a bad EGR pipe and since i was having problems with it anyway i capped it and bought the doggie collar for the upper hose which was loose as well.

took it on a test drive thinking it would be good and noise was still there. so that was disappointing and i was thinking damn it is the turbo for sure.

the turbo looked good though, all blades fine, no excess play and i have seen bad ones before so it just seemed weird and i though i would look again.

checked lower boost hose, was a bit loose but not bad. no real mess around it either. everything else clean and dry. no signs of a leak except for i noticed back of the block had a bit of oil on it. thought it was from careless oil change refill but it looked fresh.


well long story short, i was checking my block off plates and they were good and clean i thought i saw intake manifold sort of flex when i was jamming my arm behind it to check plates. I then tried to move it and thought it was almost imperceptible i could swear i could move it just a tiny bit


i found the bolts that hold it on via picture and stuck a ratchet in to check them and damn if several weren't slightly loose. tightened them down, took
it for a drive and voila! no more noise.


so the moral of the story is, your intake manifold may work itself lose and make a nasty boost leak, other culprits of course remain upper and lower boost hose, intercooler and EGR hoses but one thing i was not prepared for was the intake manifold being ever so slightly loose.

as far as i know this intake manifold has never been off. first one i have ever had sort of work itself loose.

hope it helps someone.
 
Last edited:

Lurker92

Veteran Member
Joined
Mar 5, 2013
Location
Airdrie Alberta
TDI
2004 Jetta TDI, 2002 Golf TDI
Thanks for this, I just recently started having a similar issue.

Completely losing boost for a few seconds and then it comes right back without cycling the key, so not limp mode but feels like it. No codes so far either so I’ll add this to my things to check!
 
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