White smoke, loss of coolant.

[Mr04vea]

Hi all, on a leisurely drive today taking in the sunshine I pulled over to have a quick drink and talk with a friend. After leaving the car for 10 mins, when I returned I was greeted with a lot of white smoke and a warning saying to stop engine and check coolant. I did and the bottle was empty. As I was in the middle of no where with no phone signal, I filled the coolant up with water from my bottle and headed home ASAP. After a few miles the smoke cleared and the coolant lasted. As I was pulling onto my drive the coolant light came on again. Topped up and started the engine and hello smoke.

Car is a 2014 A4 B8 facelift. 2.0tdie 136.

Now I thought the days of head gaskets blowing were gone in modern day cars but I may be wrong.

There doesn't seem to be an rise in oil, no white gunk in the oil cap so I assume water is leaking into one of the cylinders? No loss of power at all.

 

I've also read it may be the EGR Cooler that's cracked. Is there any way to test either the head gasket or cooler? The coolant pipes don't seem to be pressurised so much when squeezed. 

Any opinions?

Thanks! 

[Magnet]

Hello Dave.

Thanks for being in touch with the forum, and sorry to hear of your issue. 
All we know is that you are losing coolant. The task now comes to finding where it is leaking, and not to assume anything (suspect head gasket included) until you have eliminated any external leaks. A basic start is to place newspaper or similar ( weighted down) under the car, following its last trip of the day, and look for wet patches in the morning.

Kind regards,

Gareth. 

[Mr04vea]

Hi Gareth. 

 

Thanks for your suggestion. There's no coolant leaking externally. If there would be, I don't think I would have any white smoke from the tips. 

 

My day has consisted of conducting tests on the car to try and determine whether its the head gasket/cracked head or the EGR Cooler. 

 

I made a bypass for the cooler to eliminate any water passing through it and after a drive, the coolant hadn't moved from full. I then connected the cooler back up and 2 miles down the road it was below minimum. I decided to try again, this time leaving the coolant on minimum and bypassed and it never moved. 

 

This has brought me to believe the cooler is at fault. It looks fairly straight forward to replace. A few hex and hoses and out she comes. 

The only concern I have is while the bypass was in place, smoke was still pouring from the rear. While the coolant not moving was reassuring its not the head, coolant is indeed still being burned from somewhere. 

Now my question is could there be an amount of water sitting somewhere still burning away, possibly in the exhaust? Or could the cooler still be seeping water from whats left over when I did the bypass? I would love to hear of anyone who has done this before and how long it took the coolant to eventually burn up? 

 

Thanks!

[Magnet]

Hello Dave,

’...coolant never moved...’. Simple logic - if it isn’t losing coolant with the cooler by passed, then it cannot be burning coolant! 
Kind regards,

Gareth.m

[Mr04vea]

Hi Gareth, so with the cooler not bypassed and running normal. Coolant is lost at around 100ml every 10 minutes. With it bypassed, not coolant is lost. 

 

Is it possible that there could be coolant still in either the exhaust system or whatever remained in the cooler after I bypassed it?

 

I have picked up a cooler from GSF for £408 with surcharge. Going to attempt to get it fitted after work. A few garages I have spoken to have said it could take up to two weeks for the smoke to dissappear. 

 

Thanks. 

[Magnet]

Hello Dave,

The fact is you have to replace this faulty component, and it’s reasonable to expect that there will be some residual moisture in the exhaust. 
A couple of weeks for the white smoke to disappear? If a few garages have told you that, then you have to go with that opinion. Seems a rather long period of time to me, but I will now to their experience. 
I guess it’s a question of replacing it , and see what happens - on the basis that you only have to worry about one thing at one time.

Perhaps you would let us know how you get on.

Kind regards,

Gareth.