A4 Coolant loss

[leej]

I have been getting a coolant loss warning every couple of days now, this has been going on for a while. I have filled with coolant and left the car running idle on the driveway looking for the loss any ideas????? as nothing is visually being lost

[RickT]

How old is the car?? i take it, its a B7?

Which engine is it?

Rick

[leej]

the car is registered in 2001 but it's had a bit of work done:
new cat, exhaust, turbo and a new engine at around 120k the car has now done 150k
it's beginning to do my head in as it's been in a local garage for a couple of days and they cannot find anything wrong with it
one thing i didn't mention is that the engine management light has been on for about 10 montyhs but I have recently (about 4 months ago) had it serviced by Audi and they couldn't find the reason why the engine managment light was on but said not to be too concerned

[moonbug]

Hi,

Long shot I know as this is a very old post - but did you ever get to the bottom of this?

I have the same issue - coolant warning light every couple of days and garage which say that they can't find a leak.

[fourringsrus]

sensors

[moonbug]

Sadly though I am actually loosing coolant - I have to top up by 500ml every 300 miles - I assume there is no way this could be down to a sensor?

[a8 tech]

Run the engine to temp then allow to cool
connect a coolant pressure tester and set to 1 bar
leave it for 24 hours and then check for leaks

If its a 1.8 turbo look behind the water pump housing above the thermostat beneath the alternator area and there is a small pipe/bung that leaks.

At the side of the inlet manifold there is a black metal coolant pipe with a bleed screw, the screw breaks allowing coolant to seep

Remove the front bumper and inspect the radiator end caps.

If still no leaks then check coolant flow at the header tank

If the flow is not constant then inspect the water pump and also ensure the flow through the radiator is good.

Failing all this check the hydro carbons in the coolant for internal combustion leak (head gasket) rare but possible

[blacksline]

Funny you should mention this - I've got similar issue on my A4.

Was serviced by 4Rings a few months back, and they said my coolant hose was leaking. They didnt have a hose with them so they advised I seal it. I literally just checked under my hood, it appears the hose has started to leak again. It looks like an easy DIY repair, and i been trying to source the part online, but having no joy. Does anyone know where i can order an hose from? or would i need to buy it from Audi itself??

Thanks,

Run the engine to temp then allow to cool
connect a coolant pressure tester and set to 1 bar
leave it for 24 hours and then check for leaks

If its a 1.8 turbo look behind the water pump housing above the thermostat beneath the alternator area and there is a small pipe/bung that leaks.

At the side of the inlet manifold there is a black metal coolant pipe with a bleed screw, the screw breaks allowing coolant to seep

Remove the front bumper and inspect the radiator end caps.

If still no leaks then check coolant flow at the header tank

If the flow is not constant then inspect the water pump and also ensure the flow through the radiator is good.

Failing all this check the hydro carbons in the coolant for internal combustion leak (head gasket) rare but possible

[a8 tech]

audi only

[moonbug]

Run the engine to temp then allow to cool
connect a coolant pressure tester and set to 1 bar
leave it for 24 hours and then check for leaks

If its a 1.8 turbo look behind the water pump housing above the thermostat beneath the alternator area and there is a small pipe/bung that leaks.

At the side of the inlet manifold there is a black metal coolant pipe with a bleed screw, the screw breaks allowing coolant to seep

Remove the front bumper and inspect the radiator end caps.

If still no leaks then check coolant flow at the header tank

If the flow is not constant then inspect the water pump and also ensure the flow through the radiator is good.

Failing all this check the hydro carbons in the coolant for internal combustion leak (head gasket) rare but possible

Cheers for the advice A8 Tech - I'll get all that checked out and hopefully report back with success.