1.8T k03 Wastegate flapper

[Major Tom]

So today I finally got the turbo out (fun times, as expected), and the waste gate flapper is present and correct! When I popped the down pipe off to take a peek last week I must've been looking at the turbine area rather than the flapper. Anyway. Answering that question only leaves more questions as to what's going with the car...

I retested the waste gate of my turbo and Lito's back to back and they seem to be working fine. My turbo seems clean and in relatively good condition for a car of 257,000km's, I was quite surprised.

BUT what I have found is that the downpipe has two big cracks along separate welds, with each stretching around about 40% of the circumference of the pipe. Going to take this to an exhaust shop and get it assessed/fixed tomorrow. My exhaust does not have any flex pipe sections in it, and I suspect the combination of increased power, stock engine mounts and no flex in the exhaust had led the down pipe to cracking.

Given that the car is out of action anyway, I've taken the liberty of disassembling some other parts of the car. I've removed the whole exhaust system, bumper, intercooler and all induction piping, removed the valve cover to check the cam chain tensioner.

Things I've found on my travels:
-The radiator mounts are both broken on one side, appears as though the tab that normally sits inside the mount on the bottom left was never actually assembled correctly, which explains the little bit of radiator movement I had noticed.
-Coolant 3-Y piece broke on me while removing a hose

Getting the turbo back in will be interesting.. Some of those oil and coolant lines are pretty tricky to finesse into place.

[h100vw]

So today I finally got the turbo out (fun times, as expected), and the waste gate flapper is present and correct! When I popped the down pipe off to take a peek last week I must've been looking at the turbine area rather than the flapper. Anyway. Answering that question only leaves more questions as to what's going with the car...

I retested the waste gate of my turbo and Lito's back to back and they seem to be working fine. My turbo seems clean and in relatively good condition for a car of 257,000km's, I was quite surprised.

BUT what I have found is that the downpipe has two big cracks along separate welds, with each stretching around about 40% of the circumference of the pipe. Going to take this to an exhaust shop and get it assessed/fixed tomorrow. My exhaust does not have any flex pipe sections in it, and I suspect the combination of increased power, stock engine mounts and no flex in the exhaust had led the down pipe to cracking.

Given that the car is out of action anyway, I've taken the liberty of disassembling some other parts of the car. I've removed the whole exhaust system, bumper, intercooler and all induction piping, removed the valve cover to check the cam chain tensioner.

Things I've found on my travels:
-The radiator mounts are both broken on one side, appears as though the tab that normally sits inside the mount on the bottom left was never actually assembled correctly, which explains the little bit of radiator movement I had noticed.
-Coolant 3-Y piece broke on me while removing a hose

Getting the turbo back in will be interesting.. Some of those oil and coolant lines are pretty tricky to finesse into place.

Is it a big bore downpipe? I guess it is if there's no flexi section. Be pretty smart to have one fitted. You will probably find it easier to disconnect the oil feed at the front of the engine and do up the turbo end first, before you bolt the turbo to the manifold. Same with the water line.

403 Forbidden Got one of these in my cupboard if that's the one you broke. Lito got a plastic one, I think it lasted about 10minutes. He then got a VW one and that's stayed good.

Gavin

[Major Tom]

Yep Gav it'd be 2.75" or 3" right through, I will measure tomorrow. Going to chuck it in the backpack and ride over to Albion Mufflers tomorrow and see if they can install a flex section and weld it up.

The coolant part that broke was on the on the transmission side of the engine, above the starter. P/N 1J0121087A, which I will order from Austral tomorrow.

Thanks for the advice re oil/coolant lines. I was thinking the same thing. Disconnected the oil line from the filter housing so that I could wiggle the turbo enough to get an allen key into the banjo bolts on the turbo. Exhaust manifold is still in place.

Been a long night in the emergency department after the cat back fell on my fingers. Nothing broken but some swollen joints to enjoy!

[007]

Sorry to hear about your injury - hope you're on the mend. While you've got things apart, check your N75 wastegate regulator valve. The procedure is here. There is a really useful discussion about the N75 on the audi forums here.. Given the K's yours has travelled, (keep in mind it works harder when the car is chipped) it would be well worth having a look at it. They don't last forever. I can tell you that my turbo was surging and so I replaced the N75 and DV together and felt like I was driving a new car afterwards. Keep us posted on your progress!

[h100vw]

Yep Gav it'd be 2.75" or 3" right through, I will measure tomorrow. Going to chuck it in the backpack and ride over to Albion Mufflers tomorrow and see if they can install a flex section and weld it up.

The coolant part that broke was on the on the transmission side of the engine, above the starter. P/N 1J0121087A, which I will order from Austral tomorrow.

Thanks for the advice re oil/coolant lines. I was thinking the same thing. Disconnected the oil line from the filter housing so that I could wiggle the turbo enough to get an allen key into the banjo bolts on the turbo. Exhaust manifold is still in place.

Been a long night in the emergency department after the cat back fell on my fingers. Nothing broken but some swollen joints to enjoy!

Hope the fingers heal quick.

I like the exhaust in the backpack, pushy to the exhaust shop bit.

Many moons ago, after my AE86 with 4A-GE boiled over. I took the head to be skimmed in a backpack on my GSXR750.

I was also thinking maybe the N75 is crook. They usually fail open and you get wastegate pressure. If it failed shut, the boost would never be regulated and Chernobyl would ensue.

If you need any help let me know.

Gavin

[Major Tom]

Thanks for the tips guys!

Hoping to get the car totally back together today. Just taking my time, cleaning all the intercooler piping etc. while I've got it apart.

I will look into the N75 and see what I can find.

T