Custom Exhaust & A Few problems...

[WaltD96]

After buying one of those cool little OBD readers to unlock features on the car... I ran a diagnostics and got the problem codes listed below. Are these common errors to have for the Polo GTI 6c's? (2015) if so, what usually causes the error and am I looking at DIY fix?

I've googled the code ending 500 because it says it's critical, but I've no engine light showing and the car does seem to be running fine. I was really hopping to get some mods done this month and hoping to not have to spend a fair bit on repairing whatever's wrong with it!

Problem Codes:
P256500
P050700

Also - may be a stupid question.. it's the first car I've ever modified, but I'm booking it in after the MOT in july to have a full turbo back with sports cat done by longlife - if I upgrade to an IS20 in the future (which is the plan) with the additional bolton's required, would I then need a new downpipe made to fit the turbo?

Also - I've finally found a decent set of front b8 shock absorbers being sold as a pair from Germany on eBay.. with relatively low shipping price, but they're £60 less than they are on the bilstein site.. the part numbers line up, but I'm questioning myself on as to why they're cheaper and don't want to get mugged off

[Bepis]

Are you currently stock or has a custom exhaust been fitted?

Which diagnostic tool are you using? Carly, OBDeleven, VCDS, etc

Also, do the codes come back after being cleared?

With the codes you've provided, P2565 comes back as Turbocharger Boost Control Position Sensor Circuit: Signal too High with mentions of turbo vanes. As far as I'm aware the IS12 does not have variable geometry. This code may be referring to something to do with the diverter valve or wastegate actuator.
http://wiki.ross-tech.com/wiki/index.ph ... 565/009573

P0507 is Idle Control System RPM: Higher than Expected. Idle when cold is around 1k rpm and hot is around 7-800 so that should be an easy thing to check.
http://wiki.ross-tech.com/wiki/index.ph ... 507/001287

Seems like you may have an air leak somewhere but start by clearing codes and seeing if they come back.

Some quick checks you can do:
Check that the small vacuum hose for the intake runners is connected to the airbox
Ensure the oil dipstick and cap are seated correctly
Listen for a whistling noise coming from the area around the PCV. Remove the engine cover, it's the black plastic piece sat on top of the engine in front of the coil packs with a circular section and 2 hoses coming from it.