Catch can kits for Mk5 GTI?

[maltbbe]

Thanks for this! I think those PCV delete plates don't have ports for a catch can, but otherwise this could work well. Hanging out for something used to turn up on the forums...

[brad]

Thanks for this! I think those PCV delete plates don't have ports for a catch can, but otherwise this could work well. Hanging out for something used to turn up on the forums...

If it's like the TSI then the OEM has one hose to the inlet manifold and another to the pipe just before the turbo. The delete plate has a single hose that goes to the catch can and then to the inlet pipe before the turbo. The inlet manifold connection is blocked off with the supplied bung.

[kdog]

@kdog how did you relocate the carbon canister? I've read a few threads on that but it sounds like a big job - the hoses running to it are welded plastic right?

not really, hardest job is finding where to mount the bloodying thing.

they are but if you cut it very very carefully with a sharp razor or even get a hose thats wide enough to go over the top just do that.

i can provide photos if you want how ive done it.

[maltbbe]

@brad I think FSI engines work a bit differently - the outlet and inlet for the OEM PCV valve are next to one another, so catch can adaptor plates end up looking like this: Mk5/Mk6 2.0T FSI Catch Can Conversion Plate (1/2" NPT) - 42 Draft Designs. Seems like pretty average design to me (not that I really understand how it all works lol) but I'm gonna assume it was improved on TSI engines so that the PCV valves stopped failing all the time... The single outlet left on FSI PCV delete plates clips on to the OEM breather pipe.
@kdog photos would be rad if you can! PM me if you can't upload them here

[maltbbe]

For anyone curious to know how I solved this...

I ended up getting a catch can adaptor plate and boost cap from 034Motorsport (through urotuning.com), and had 1/4inch BSP fittings tapped into the inlet and outlet bungs. I bought a Mishimoto compact catch can off Gumtree, and used some 5/8ths heater hose and fittings from Pirtek to connect the two. The whole setup cost about $350, which is way less than it would've cost to import or locally buy a complete kit (most seem to go for about $650).



Inevitably, the problem was finding somewhere to mount the thing... my plan was to mount it to a hole on the engine cover (see second photo below), but the hose was too thick to flex without kinking. Right now, it's zip-tied to the carbon canister; it's secure, but it looks real sketchy. I think I'll eventually replace all this piping with AN fittings and braided hose, and mount the can to the bolt securing the top half of the washer bottle (underneath the plug connected to the coolant overflow tank).





If anyone's looking at doing something like this, VAGparts.com.au has at least one 034Motorsport FSI adaptor plate in stock. They sell two models of these plates, one with barbed bungs and one with AN fittings; I'd 100% recommend going for the one with AN fittings, since (for some reason) it's cheaper anyway and you can spend what you save on better-quality hose. The Mishimoto can is a good option just because it's so small, and it seems to be one of the cheaper name-brand options out there.

[gazzmo]

Still trying to work out what the advantage of a catch can is, reduced carbon build up not really, looks yes they have chick pulling power...let us know how the catch can has benefited you please

[maltbbe]

I'm not an expert, but I think the idea is that with any direct injection engine you tend to get a lot of unburned oil gunk build-up, which collects built-up carbon, which makes your oil more dirty, which ends with more carbon-build up. There's meant to be a crankcase ventilation system (PCV system) that clears all this gunk out and sends it back to the intake to get re-burned, but Mk5s have a pretty ineffective PCV system, so that doesn't always happen. The gunk also gets into the turbo and intercooler piping, which can damage things; when I replaced my diverter valve, oil sludge was actually pouring out of the diverter valve housing and had seeped into the wiring. I think my car had a failed PCV valve for ages, which wouldn't have helped, but a catch can is pretty much meant to be a better PCV system (or, in the case of Mk5s - which all have pretty rubbish stock PCV valves - a PCV system that actually works as it should).

I'm hoping that having the can there will clear out all the gunk that's still in my turbo piping - it's been a week and there's already a fair bit of oil in the can. I feel like the car idles and revs more smoothly now, but that might just be my imagination... since I needed a new PCV valve anyway, this was really just preventative maintenance. There's way more Mk5-specific information online if you're keen.