Loosing coolant from expansion tank when engine is hot.

Hello All,
Has any one with a Audi A2 1.6 FSI had any problems with loosing coolant from their expansion tank, as I have.
As I was on my way to work, I noticed quite a lot of smoke from my rear view mirror. I stopped the car, and switched off engine, smoke everywhere! Loosing coolant at back of engine, over exhaust pipe.
Traced coolant leak to plastic coolant pipe at back of engine, which had split. I suppose after 11 years of wear and tear, something had to give. But, my question is this, did it go under high pressure from the system, or could it be just general wear and tear. Has anyone come across this before, and what would be the part number of the pipe which goes from the water pump, to the 7 branch coolant take -off at the end of the cylinder head?
The attachment shows the plastic coolant pipe on the block below the injectors.

Hi i have seen this pipe split before on an fsi --- and that engine had a head gasket blown. So the million dollar question "did it split causing the heard gasket failure or because of the head gasket pressurising the system"? Well in the case of my engine it was the head gasket that had gone causing it to split. On my other fsi (daily driver) i replaced that pipe the last time i had the thermostat fail.
So i would start to look for other signs of over heating. Hope that helps mike

The plastics on the hard water pipes on the A2 perish/harden with age. I have had 3 pipes fail on mine in the last 3-4 years, normally a week or three after some maintenance (ie after pipework has been disturbed).

Thanks Mike for your swift reply.
I really hope it is not the head gasket, because it is big money to fix. This pipe is this cars first, though I am sure it won't be the last. However, I will find out what it costs to be replaced, and go from there. If it is too expensive, including head gasket, I may have to get rid of the car altogether. Mine is a daily commute vehicle, so I cannot really afford to have it off the road, and is the only car I have.
Andy.

Thank for your reply chb.
Yes, coolant pipes do harden with age. It seems a shame to have designed a system with a coolant pipe at the back of the engine,,,it's fine for production, but, when joe public works on their car, or garage mechanic, the becomes more difficult, and more expensive. I will have to see how I get on with a new pipe fitted.

Hi Mike,
I have now replaced the split coolant pipe. The split pipe actually had very small cracks in it which are very hard to see, but they are just about visible. I really hope this cures the problem, although I have checked elsewhere for leaks, I hope it is not the head gasket!
As Audi wanted £500 for replacing the pipe, I did the job myself, but took most of the day to do it. Anyway, I hope all goes well. Will keep you posted.

Hi

Plastic pipe from thermostat housing to the water pump area is a right bu&&er to do.

If it was that one that went, and you did it without a ramp, you sir, deserve a medal!

Hi mrtutz,
Yes, it was a very difficult job to do, and I only had a hydraulic jack and an axle stand. The worst part was taking off the bracket which is attached by four bolts, at the back of the engine. I did not even have to detach the right hand drive shaft from the gear box. Luckily, everything went ok. The other thing was to attach gear linkages,and get everything working, but, eventually all was fine. I still have to keep an eye my coolant though, no leaks, but, it still sometimes comes out on the overflow of the expansion tank.
.

Just a quick question what did you use for support when you took off the four bolt support bracket?

If memory serves me right you don't need anything to support the engine when you take off the bracket. It goes in between the block and the inlet manifold as I recall. I'm assuming it's a support bracket for the inlet manifold.

I didn't undo the 1/2 shaft either, as I didn't think the extra space was usable in changing the pipe. It's worth putting a thermostat housing on while it's stripped, as these are prone to failure too.

Cheers