2003 2.0 8v AZJ Water leak, possible oil leak, advice needed

[2001gti]

Hi people

Ok, so I have a 2003 2.0 8v Gti, I love it, brilliant car, heated leather interior, climatronic etc, drives great too, but .... yesterday ... not so great ....

Stop warning light and the water symbol flashing. 2 miles to the turn off and a petrol station, didnt think much of since my last ti did this frequently, however,this was different.

There is a metal pipe (a t piece) part of the coolant system, that sits on the front of the engine as you look at it front in front of the car, under the inlet manifold, almost looks like it goes into the block (like it sits between two bits of the block that stick out and then the t piece comes out from the centre of that to face the front of the car and then bends off.

Anyway, where that t piece comes off it has cracked underneath and water is pissing out of it. Can tell how much, but alot, there may be ilittle left and i havent driven it since.

Hard to get at, i will be doing a lot of dismanting for sure, just bought a haynes manual.

Having taken the plastic shroud of the top of the engine today and had a quick gander, there is also quite a bit of oil. I cant tell how fresh until i get various bits of air intake etc out of the way so hoping i haven't warped the head or something horrible like that. It did get f**king hot! Even if only for a short time.

Anyway, cash is short and I'll be fixing it myself. Im pretty handy with a spanner i hope, i built a kit car 20 years ago but ... not so much on modern cars - this isnt a 1.6 ford pinto by any stretch of the imagination, hence the haynes manual.

So ... any advice welcomed. Until the haynes manual turns up i don't even know what this metal pipe is apart from 'a part of the coolant system' ... somewhere between the heat exchangers and the overflow resevoir (i think).

My plan is to strip it down as per the manual, top it up with coolant / antifreeze and hope i havent blown the head gasket. Not sure if i can obviously tell if I have until i get it running, thoguh the oil could be a tell tale sign?

I mean, ive never had a car do this to me in all my years driving so i dont actually know what might happen head gasket wise. IS it possible on this car to drive for 2 miles with no water (50 mph 5th gear gentle cruising) and blow a gasket or war a head so much that oil pisses out from it. Oil is all over the rocker cover though i cant see how fresh, and would oil piss upwards from head gasket up over the rocker cover?

[lemski]

Cant see it being head.
Rocker gasket most likely.

That water pipe should go to the heater matric from the block and to the reservoir.
40 quid maybe. They always rot out eventually.
My mk2 needs one...

Easy enough though, couple of 10mm bolts to release it and the water pipes. O ring should be where it goes into the block.
(im thinking of a 1.8t, never really had much to do with the  2 litre)

Hope this helps

[2001gti]

Cheers for the reply. I have another question.

So I changed the pipe, was a ball ache to be honest ... radiator hoses all tough to shift which took an age and had to remove a couple of other electric bits which weer in the way / unclip a lot of cables and remove a couple of mounts.

Anyway ... I've just done 20 miles in it, no leaks! no overheating! Doesn't seem like it's loosing water at all so seems the head gasket is ok ...BUT ....

... I have a strange idle now and a noise of air either being sucked or blown somewhere near the brake master cylinder.

The car runs perfect, drives perfect, engine is sweet as a nut but driving on a long straight for example you can see the temperature gauge dropping to about 70, when you get to traffic lights or pull up with it running its back up to a normal 90 degrees.

My instinct is telling me its something to do with the thermostat but I can't fathom this air noise. When you turn the engine off its a real hissing for 3 or 4 seconds after the cutting the ignition.

Any ideas?

I see a pipe running from the air intake assembly to the expansion tank so perhaps related to that? Might there be an airlock which is causing all these symptoms?

I ran it for 10 miles with just clean water then opened the drain valve let water drop to near bottom of expansion tank, refilled, (did these 3 or 4 times) then stuck in a load of antifreeze. Another 10 miles, still no water loss.

Thats all I got? Any ideas welcomed

[2001gti]

ok well .... have time today to have another look at it. Prime suspect is that pipe I mentioned ... it runs from expansion tank to throttle control valve ... sounds like a prime candidate! Fingers crossed that pipe got hot and damaged when I broke down and it's as simple as that. The air noise was coming from right around there so i'm optimistic ...

As for the temperature running cool .... I removed the sensors that bolt onto the block itself which I guess are temperature sensors (haynes manual still not arrived! grrr ebay) when I stripped everything down. Didn't really think I could go wrong bolting them back on and was pretty careful with the wiring and plugs so would be irritating if I have damaged a wire.

Before the breakdown the car would sometimes run below 90 degrees (which seems to be normal operating temp in all conditions) and I wondered if maybe there was a thermostat issue. This is different though, like a half mile straight and it will drop from 90 degrees to maybe 60 or less. There is no way the block itself could cool to that extent in that period of time in any circumstance so I am confused. Seems a false reading unless ... i dunno, maybe one of those sensors is actually faulty or there is a gap between it and the block and air is rushing round it cooling the temperature quickly?

Just guessing here but if anyone has any ideas, i'd love to hear them, cheers

[2001gti]

It was the hose running to the master cylinder. Looks like where it push fits on the heat had shrunkthe pipe a bit and it had split. Have to replace it but just duck taped the split for now and whadda you know .... perfect idle and quite bizarrely ... temperature seems to sit at 90 again, or close enough (though only did a few miles).

Result!

[lemski]

Vaccum pipe? Well done for sorting

[2001gti]

Yep vacuum pipe. Its running great now, but, temperature still isn't. I need to check out those two sensors that bolt on to the block. Not a big issue but a bit irritating.