Audi A6 2.5Tdi excessive white/grey/slight blue smoke, loosing coolant

[ash1983]

hi all, i've got a a6 2.5tdi on a 98S plate and i'm regularly topping up the coolant and i'm getting loads of greyish smoke with a tint of blue. the oil levels are ok. It's not all the time, it's mainly when i stop at traffic lights. It's quite bad, i actually leave a cloud of smoke when i pull away at the lights I've bin told its smells of diesel.
The performance is fine and it's probabily even better since i replaced a faulty coolant temp sensor.

The turbo also seems to be running fine, i've done some reading an suggest its a blocked crank breather filter but seems a fiddly job so i'll be tempted to just give it in to a garage however i've had bad experiences with some garages. i just needed some advice on what it could be from fellow Audi owner first.

Any help appreciated thanks
Ash

 

[nora2004]

If your having to top up the coolant, then im afraid your loosing water somewhere! Try taking off your oil cap when the engine iss off and look for a whitey creamy substance on it, if you do see that then it could be possible head gasket failure!

It could be something as simple as a leaking hose, radiator, thermostat!

Other symptoms of a failing HG is a white smoke coming from the exhaust, its exactly that, white, not grey or blue, does it still produce this smoke after the car has been driven for a long period of time?

Whilst under the bonnet undo the cap off the header tank, have a smell of the water, check the color and report back!

Are you loosing oil? As blue smelly smoke is normally indicating your engine is burning oil, how many miles has your car done?

 

[ash1983]

I've had a look under the oil filler cap and there's no creamy substance. I'm hoping it's not the thermostat as ive had it replaced within the past year and the car seems to be heating up well.
I'll monitor the oil level to see if it's going down.
The cars on 95,000 mls at the moment, i removed the oil filler cap after a long drive to hear for any hissing or like a pop indicating it's under pressure but didnt hear anything it just seems more like it was on a vacuum, so i'd be tempted to replace the crang breather filter if it wer'nt such an arqward job.