Ok...I'm confused, and Rob is confused..

We've been looking at part diagrams....

Simple question.... Which way does the air flow in the system?

1. From the turbo, to the bottom of the IC, out the top, up to the left side of the engine bay, through the EGR and into the intake?

2. From the turbo, through the EGR, down the left side of the engine bay, into the top of the intercooler, out the bottom and into the intake?

Becasue, I'll just add....

If it's diagram A, at the top..... How does the EGR mess up the pipe work before it?

Option 1.

Phil

Hmm I've wondered this too lol

Edited 29 November, 201213 yr by DanHam

Becasue, I'll just add....

If it's diagram A, at the top..... How does the EGR mess up the pipe work before it?

It doesn't.

Any oil in the pipe before the EGR comes from crank case breather at the other side of the turbo.

Phil

So the gunky pipe work is always pictures of the EGR? Coulda' sworn I'd seen gunky IC's and pipes...

But yeah.. I guess it is, in hindsight...

Think of whats attached to either side of that diagram.

intake -> airbox -> EGR -> into the top of the pipework in the diagram -> through the IC -> to the turbo -> to the engine

Turbo doesn't suck hot air out of the enigne to be cooled by the IC!

Absolutle classic!!!

Think of whats attached to either side of that diagram.

intake -> airbox -> EGR -> into the top of the pipework in the diagram -> through the IC -> to the turbo -> to the engine

Turbo doesn't suck hot air out of the enigne to be colled by the IC!

Haha. Yeh it would be trying to suck air OUT of the engine and blow it out through the air filter. lol

Plus just think what the EGR is attached to... the intake manifold. That gives it all away.

Phil

As far as i know the gunk in the pipes is because of the EGR

Again think what it does - It recirculates exhaust gases.

Thoses gases get passed back through the system to attempt to use any unburnt fuel, the burnt fuel (ie soot) in the reirculated gas creates the gunk, gravity makes it pool in the IC if it builds up enough.

Yeah, but if the gases are being injected right before the intake, surely they'd go into the intake, get burnt with the fuel, then go out of the exhaust, and not end up going back down a pressurised system that's flowing the other way?

I've never seen a really gunked up IC or other boost pipes. It's the EGR valve that gets really bad.

Any oil or gunk in the other parts of the system will be from the breather pipe which is on the metal intake pipe after the EGR.

Phil

So the Elephant mod is ment to cure this. Could it also be said then that the Elephant mod is good for the turbo?.

Yeah, but if the gases are being injected right before the intake

I thought the removed exhaust gases were put back into the boost pipes and went through the whole system again rather than just going from exhaust manifold to intake manifold.

I thought that that was where the gunk comes from.

I thought I knew what i was talking about!

This diagram of airflow in a turbo actually mkaes things worse in my head!

oh this one has flames and ice so MUST be better

Haha you can see why I got confused...

oh oh oh

ignore the supercharger but this might be a simplied full air flow diagram

so working round the diagram(s) gives us

Fabia airflow:

in the intake in the grill

through the air filter in the inbox

down to, and through, the turbo compressor

through pipework to the intercooler

in to the intake manifold

through the engine

out the exhaust manifold

through other side of the turbot

through the cat

out the exhaust

on that basis the EGR takes gas ouf of the exhaust manifold and puts it back in to the system after the compressor but before the intake manifold allowing the unburnt gases to go throgh the engine again......

....maybe!

It's the inlet manifold that gets gunked up, because that's after the EGR.. Boost hoses just get oil in them.

So to add to Cliff's post...

in the intake in the grill

through the air filter in the inbox

*Breather from cam cover added into airflow (Oil vapour)

down to, and through, the turbo compressor

through pipework to the intercooler

*Through EGR valve, (exhaust gas added by ECU)

in to the intake manifold

through the engine

out the exhaust manifold

*Out through take off to EGR valve

through turbine side of the turbo

through the cat

out the exhaust

The "gunk" issue lies between these lines.

*Through EGR valve, (exhaust gas added by ECU)

in to the intake manifold

through the engine

out the exhaust manifold

*Out through take off to EGR valve

I think I understand now

Cheers guys.

It's the inlet manifold that gets gunked up, because that's after the EGR.. Boost hoses just get oil in them.

this is exactly correct.

I had a boost hose blow off yesterday (on the motorway), where the top gasket marked 23 on the diagram is, and it spewed oil all over the hoses and the corner of the engine bay. Thankfully It was a simple fix and as i was doing it i had a look inside the pipes, they're oily but not coked up like the EGR/inlet manifold gets.

The elephant mod is next on the cards for me, i'll need to find somewhere for a suitable catch tank.

Also, i could feel the air rushing out towards me even with the car at idle, so it's definitely the way noted in your first diagram.