PDA

View Full Version : Losing Coolant



tonya2
22-01-2007, 09:43 AM
I own an A2 and for months now, I keep getting the low coolant warning light. I check the coolant, and its low, so i top it up. This has happened for about 4 months now in total.

I have taken the car to the garage 4 times (twice to an Audi main dealer) and nobody can diagnose the problem. Someone has told me it might be the head gasket on its way, but no garage has been able to confirm that yet and there are no obvious symptoms that i can see.

Until recently, nobody could find where the coolant was going, but i've managed now to see that the coolant is being forced out of the coolant reservoir through the small release hole at the top. It seems that as i'm driving, the pressure building up inside the cooling system is enough to force the coolant out (is there supposed to be so much pressure?).

Audi have suggested that they need to strip the engine at a cost of about £400, just to see what the problem could be, so i'd rather not have to do that.

Has anyone had a similar problem with an A2 or any other Audi as i'm really worried that continuing to drive it will cause serious damage, but i dont have any other choice at the minute.

onzarob
22-01-2007, 08:28 PM
Has the pressure cap been changed? as it can go faulty and release pressure before it is supposed too. Audi should have done this and a presure test on the system

There was a post on here were someone was losing water and it did eventully get diagnosed as the head gasket. it was only a minor loss and he had no major signs of gasket failure. so it may be your only option.

You don't say what year and engine type your A2 is, that will help people answer your problem.

Good luck

Rob:biglaugh:

RJS_90q
22-01-2007, 10:28 PM
Is the part that you have identified as leaking the coolant the removable cap ? If so, it is possibly worth replacing this as a starting point (much cheaper than a head gasket). It may or may not be the issue, such problems are complex...

A couple of questions:-
1)Does the temperature gauge rise above the normal position in general driving?
2)If you let the car idle and the temperature gauge rises, does the radiator fan start to operate? You should be able to hear it, be careful -do not place your hands anywhere near it as it can start without any warning - best to listen for it, for safetys sake standing clear with the bonnet closed.

When driving, you should keep an eye on the temperature gauge, do not run the car if it becomes too hot as engine damage can occur.

A garage should have diagnostic equipment to completely understand the problem but the above checks may save you some cash.

Hope that this helps.

tonya2
02-02-2007, 09:39 AM
The car is a 2001 TDI SE.

I've already replace the cap and altough it did seem to initially improve things, it's still pretty much the same now really.

As for the temperature guage, well this doesn't change. I travel at least 1500 miles a month, including quite a bit of motorway driving and the temp has never gone above normal, it has never overheated either.

A few people have said it could be head gasket but most garages have said that they would need to take the head off to check and just that alone will cost hundreds.

onzarob
02-02-2007, 09:58 AM
If you changed to cap and it still going down, and the car is running ok. I wouldn't worry to much. If could be loosinf a little from one of the pipe connections, or the head gasket. But if is running well wait until the problem stops you driving. then you'll have a better idea. My MK1 golf water level slowly dropped over about 2 months. I would top it up and carry on, did 10,000 and still no problem!!!

How often do you top it up?

tonya2
02-02-2007, 11:58 AM
I'm not sure i want to wait till the car breaks down before i get it fixed although i might not have any choice.

like i said, i did replace the cap but the problem is still there. one thing i did notice is the pressure on the hoses. the hoses are very tight and i recently did a test where i tied a rag to the coolant resevior and drove for 2 days then checked the rag. the rag was full of coolant so the water is being forced out of the little release hole at the top of the coolant resevoir.

not sure if the pressure in the hoses is supposed to be like that or there is a problem with the coolant reservior itself.

i really dont lose that much coolant. i can sometimes drive around for a week without topping up.

people still tell me it could be the head gasket but no garage can actually find a fault, not even audi.

passat boy
02-02-2007, 12:35 PM
I'm not sure i want to wait till the car breaks down before i get it fixed although i might not have any choice.

like i said, i did replace the cap but the problem is still there. one thing i did notice is the pressure on the hoses. the hoses are very tight and i recently did a test where i tied a rag to the coolant resevior and drove for 2 days then checked the rag. the rag was full of coolant so the water is being forced out of the little release hole at the top of the coolant resevoir.

not sure if the pressure in the hoses is supposed to be like that or there is a problem with the coolant reservior itself.

i really dont lose that much coolant. i can sometimes drive around for a week without topping up.

people still tell me it could be the head gasket but no garage can actually find a fault, not even audi.


Have you tried upping the dose of antifreeze when refilling your coolant after it shows low,use pure antifreeze only and the result will be blue cristal type streaks wherever the fluid is leaking from which the rogues you went to should have tried and then theres a cheap tool from halfords at £40 roughly that uses dye in a tube and connected to the filler bottle in place of the cap you run the engine and if the colour goes dark or black then a headgasket failure is confirmed.common leaks occur near the waterpump/thermostat housing/all hose clamp connections/any plastic coolent pipe connectors or core plugs but thats rare.on my passat 1.8t 1998 there is a tiny leak near the cambelt but behind the cover that is nearly impossible to see but after a clean and dab of johnsonns baby powder i found the leak which occured only after a very long trip.on another point as you say coolent is forced out of the cap,how about replacing the thermostat(£12 maindealer/£7 halfords) and flushing your coolent system as you dont state the service history etc.lastly dont let muppets do anything to your engine if they cant even do a basic dye test or compression check for headgasket faults.if you go to a poundland store or similar buy 151 white grease(a spray that dries to a white dry film)and spray it on every clamp and hose connection and waterpump gasket area etc leaks will leave a yellow stain(white grease turns yellow when mixed with water)thats my cheapie diagnostic for leaks.this grease does not damage any rubber or other seals etc.

onzarob
02-02-2007, 01:03 PM
Well done Passat boy, I think that explains it well and also shows that diagnosing a leak is not a quick job. just requires time. On the pipes getting presurised they should be some pressure for the cooling to work, but if the pressure gets to high then the cap releases the pressure. This is what is happening as proved by your rag test.

I would be suspecting the head gasket rather than a straight leak as the hoses are presurised. with a leak you tend to get low pressure.

Hope it helps, topping up once a week is a little too often to ignore.

Rob:D

Captain Answer
09-02-2007, 08:03 AM
Not sure how the A3 is set up, but i've had similar problems on other cars, are there any screws in the pipes (usually at the top of the system) to allow any airlocks to be cleared? If so i'd run the car up to temperature and open them a little with a screwdriver to see if air comes out. If air builds up in the system it can cause a rise in pressure and force the coolant out of the system as it expands :Blush: