MK5 GTI DSG Clunk/Juddering Issue

[Levi]

After reading hours trough the forum topics looking for some answers to my problems I've decided I should make my own post. Last summer got myself a Mk5 Gti with 180.000 Km (110.000 Miles) as I was expecting it came with some problems, took care of them nothing to be scared about. Back then I didn't drive the car in manual mode for some reason so I can't be sure that my issues with the dsg trans were there from the beginning. My problem is that the moment I go in manual mode and change gears at about 3k rpm I get some judder like the whole engine is moving. I also get a pretty big clunk when my car is downshifting from 3 to 2 gear but I can blame that on my possibly original dmf (he's a bit of a loud boy). The car is also dropping in rpm when breaking hard, it goes down to like 500 rpm and then back up, never stalls tho. When I'm putting in gear it also likes to make a clunk and shake the car a little bit. Went to the mechanic he told me the dmf is fine for now, changed one transmission mount and told me that every other engine/trans mounts are okay, that's it. I've been driving like this for the past 3-4 months saving up for dmf + clutches.


Things that I've done so far:

Timing belt
Cam chain
Water pump
Spark plugs
Coil pack
Pcv valve
Diverter valve
Dsg oil change at 182.000 Km
Every filter got changed
Vcds reset (One thing to mention, gearbox takes like 30 minutes drive to get to 50-60 degrees which I find strange because the gearbox is using the engine coolant to transfer heat, asked the mechanic about it and he said it's fine)
Main Thermostat
Dsg Thermostat


Things that may be the cause after reading trough the forum:

Cracked air filter housing
Maybe spark plugs?
Dmf + clutches
Mechatronic (never had problems with changing gears, it only clunks)


I'm really confused and I have no idea.

[GreigC]

It sounds like a separate issue from DSG. (By the description)

When you mention low RPMS it sounds like PCV/boost leak. Might be worth doing a smoke test of the rest of the boost vacuum hoses and visually checking your PCV body is tight to the engine…. visually check all your PVC/Boost hoses for cracks/splits.

A little test for PCV start the car. Whilst the car is idling unscrew the oil cap. If you can’t lift it because of pressure it’s most likely a PCV issue. If it lifts off no problem whilst car is idling then most likely your PCV is fine.

How old is your dip stick? If it’s orange (original) it’s most likely cracked/missing its o-ring seal this can cause a small vacuum leak… or worse once cracked small parts falling into the oil sump.

The DSG is clunky/noisy even when working properly. If it’s excessively loud. Usually indicates worn clutch pack.

[Levi]

Thank you for your detailed answer, I made a video but by what you said I think some hoses are cracked because I changed the pcv valve last year in september.

And about the gearbox, I think my clutches are almost done my car slips in second gear trying to find the biting point until it bites.

[GreigC]

Your PCV seems fine in that video. You do have the old orange dipstick. (Which does not look cracked and it still has the o-ring seal) but they are very prone to breaking into the sump (new one is yellow) Before diving into the clutchpacks, perform a leak test on your boost hoses, check your gearbox/engine mounts/dog bone/subframe. Also run VAGCOM again check for new codes the car might tell you a hidden issue. (Some engine issues can make you think DSG is at fault when it’s not) eg - worn/tired/leaking injectors. (Although this does not always show a code)

[Levi]

Again thank you for your detailed answer. Last year had a cheap obd reader and it was peaking at like 1.4 bar holding 1.1 so I'm not sure about a boost leak, but afterwards I have a strange turbo sound under load (above 2k rpms). Now that I have vcds I can check the boost levels and I'll look under the hood for cracks/splits in the boosting pipes. Had a look some time ago but I looked for oil on the pipes, nothing. I'll also change the dipstick as a precaution measure. Think there is also a way to measure injectors with vcds and I'm gonna check it.

Video:

[GreigC]

I’d still recommend doing the checks I said above first… before diving into the clutch packs. If it were the clutch packs I recon it would be the same symptoms in all gear modes. The S mode just holds each gear longer than D. D is more geared for economy.

[Levi]

I did some logging and wanted to ask if this looks right to you.






 link for detailed logging:  https://log.tunezilla.com/chart/665195#H8KLCADDp2fDsmMCA03CjUsKw4MwDETDr8KiwrUFDcO0NsOGC8K1EcKuw4DCscKCwqzClDTCp28+JGQzwot5w7PCmBjDocKtw4NLKmM2wp3DhgbDocKRw4JWFjVZGAJQKWtmwq5sw6QMB8KtXzZHV8KcwpFmw5nCrMODwqPCvsOHw59VwoFJw77DuMKuNMO2G8KIw6sYwrodw5DDpMOaw4Yifl51w4/ClMO+wp3DhH/CosKXAAAA

[GreigC]

I did some logging and wanted to ask if this looks right to you.






 link for detailed logging:  https://log.tunezilla.com/chart/665195#H8KLCADDp2fDsmMCA03CjUsKw4MwDETDr8KiwrUFDcO0NsOGC8K1EcKuw4DCscKCwqzClDTCp28+JGQzwot5w7PCmBjDocKtw4NLKmM2wp3DhgbDocKRw4JWFjVZGAJQKWtmwq5sw6QMB8KtXzZHV8KcwpFmw5nCrMODwqPCvsOHw59VwoFJw77DuMKuNMO2G8KIw6sYwrodw5DDpMOaw4Yifl51w4/ClMO+wp3DhH/CosKXAAAA

I’ll be honest I don’t understand these readings. Hopefully someone on here who knows what they’re looking at can tell if those values are correct.

[Levi]

Update :  Changed the vacuum pump because it was leaking oil, and checked the entire vacuum system no cracks or something like that but rly dirty. I've cleaned them rly good put them back in and my the problem with low rpm when braking hard is gone. Also changed the dip stick with the yellow one.

[Llew]

ive been away from here a while about 3/4 years but i had symptoms as yours and it was my dmf

[Levi]

Thank you for your information, I was also thinking dmf/clutches but I was thinking that it might have been something else. Now I know why my second gear is slipping.