Complete VW Amateur Needs Advice

[LachyH]

Hi Guys!

First time blogger - I recently bought an 05 Polo GTi from a hale auction with the intention to repair it and on-sell it.

I picked it up and discovered two things -

1. Hale had hit all panels meaning repair may be out of the question
2. It blew my head off upon discovering how much boost it was running

Based on these two factors I've decided to keep it as an everyday (but possibly sometimes track) car.

My mate (who also has a polo) says its likely I have 'Stage 1 ECU Tuning' (would make sense as its running 25 psi according to the aftermarket boost gauge).

Two further things I've discovered:

1. When I hammer it sometimes it makes a loud 'machine gun' tapping sound at the top of the rev/boost range
2. When I really hammer it through the gears it sometimes stops boosting, and the engine light flashes for a short amount of time - which I believe is to do with the exhaust.

My question is: would the downpipe/cat upgrade fix issue #2? My assumptions is that the stock manifold can't handle the amount of gas been put through it by the increased boost...but I'm no expert, you guys are!

Also I've heard there is an air intake upgrade kit? Can anyone give us details on these and if its worthwhile?

Any pointers would be greatly appreciated!

Lachy

[jabelle]

Air intake you would probably want to look at the PD160.

[h100vw]

Hi Guys!

First time blogger - I recently bought an 05 Polo GTi from a hale auction with the intention to repair it and on-sell it.

I picked it up and discovered two things -

1. Hale had hit all panels meaning repair may be out of the question
2. It blew my head off upon discovering how much boost it was running

Based on these two factors I've decided to keep it as an everyday (but possibly sometimes track) car.

My mate (who also has a polo) says its likely I have 'Stage 1 ECU Tuning' (would make sense as its running 25 psi according to the aftermarket boost gauge).

Two further things I've discovered:

1. When I hammer it sometimes it makes a loud 'machine gun' tapping sound at the top of the rev/boost range
2. When I really hammer it through the gears it sometimes stops boosting, and the engine light flashes for a short amount of time - which I believe is to do with the exhaust.

My question is: would the downpipe/cat upgrade fix issue #2? My assumptions is that the stock manifold can't handle the amount of gas been put through it by the increased boost...but I'm no expert, you guys are!

Also I've heard there is an air intake upgrade kit? Can anyone give us details on these and if its worthwhile?

Any pointers would be greatly appreciated!

Lachy

I am hoping that you aren't on a wind up here.

So with that in mind, you need to fix that boost issue before your engine blows itself apart.

Most likely the pipe to the actuator is off or split wide open. Less likely is a bad N75 valve.

Fix that first and then we'll discuss tuning.

Gavin

[LachyH]

Thanks Gavin, appreciate it!

Unfortunately not on a wind up! To be honest its quite clear previous owner didnt take very good care of the car, but I only a paid a few g for it so I guess you get what you pay for!

What boost would you recommend running to avoid blowing the engine apart?

[seangti]

Its electronically controlled. Don't worry about manual boost controllers. Check the vacuum line from your wastegate back to the 3-way T-piece that its connected and no cracks. That 3 way t-piece is the N75 valve, which means electronic boost controller. Initially, you could disconnect the controller (pull the cable out) and go for a drive to see if it still boost so high. If it does, that vacuum line is cracked. I've popped that line off the wastegate a couple of times. Best to ensure it doesn't happen.



Also scan the car for faults using VCDS. Someone local to you may be able to assist or you can download a free version and buy an ebay OBD cable to connect. Read up in the vcds section of the forum to learn so more for scanning and to make that cable work should you buy one.