Coolant Leak

[Dee-C]

Hi guys,

Bit of an annoying one and what I'm hoping wont be a costly one.

My coolant has been leaking for about 2 or 3 weeks now, it would be a very slow leak one day then the next it would just dump it all in one go.

I thought it had something to do with my climate control as it doesn't seem to be clearing my windows as well as it used to. I can get from my work to my home and windows will still be fogged up (20/25 minutes), a few months back they'd clear in a few minutes easily.
There is still good power and heat coming from the vents and I can feel the air coming out it just doesn't clear my windows. I have noticed some mornings when I start the car it sounds like running water from the passenger side vent... once I hear this I tend to check the coolant and noticed it's dropped.

I took it to my local garage who specialises in Audi/VW (Used them a few times now) and they said it was the EGR Valve. £160 for a new valve and labour... On Tue I leave work to find a puddle under the car again

It seems more central like between the front a rear seats and straight up the middle.

I've contacted the garage again but it's not back in until Saturday and after reading a few posts online I'm getting worried it could be the head gasket? leaking coolant into the exhaust manifold?

Any ideas what this might be? just so I'm a bit more prepared on Saturday and don't waste any more money.

Thanks.

[Geraldy212]

Dee, from your description, it seems like a leak in the climate control system. Specifically the heater matrix (where hot coolant circulates to warm the car). Any leak here would cause lots of condensation in the car due to the moist air being circulated. It would also give you a puddle under the centre of the car (unlike a radiator leak). Yes, the EGR valve may also be suspect, as there is an EGR cooler that is next to it. Most EGR problems are due to the buildup of carbon in the valve itself, and not usually anything to do with coolant. So I would ask the garage to carefully check the heater matrix and feeder pipes before spending money on EGR valves or worrying about head leaks. You could try turning the in-car temp right down (which should cut off the hot coolent from the heater matrix) and see if that makes a difference. If that results in a slow leak, then the heater matrix or plumbing is the problem. Good luck.

[Dee-C]

Thanks for your reply!

I'll turn the temp right down tomorrow and see if it causes the coolant to slow or stop.

I read another thread on here regarding climate control and someone mentioned it may be from a leak etc so the extra condensation from the moist air sounds right.

Sorry I made a mistake in my original post, I had a new EGR cooler not the EGR valve... had no idea they where two different parts (don't have great knowledge on cars)

I'll keep you updated and let you know how it goes on Sat.

Thanks.

[NHN]

To add, lift the seats & check under carpet for it being very wet, also feel the carpet for dampness.

[Dee-C]

Had the car in on Saturday again but the garage said they could see no signs of the leak and had checked the climate control, feeder pipes and the work they had done on the EGR cooler the week before but still no idea.
They did add some dye so they can locate the leak if it happens again.


.....First thing Monday morning I have a puddle of coolant on my driveway.


I've taken a few photos and sent to the garage as-well as booked it back in for this Saturday.

Here's one of the photos to give you guys an idea of the location. Taken from the front of the car at my work parking space (slight slope)

CoolantLeak.jpg

[NHN]

That's a biggish damp area as such, so its not small leak, ideally they should pressure test the system up to 1.5bar I reckon & see where it comes out.

[Geraldy212]

Wow, that's some leak. As NHN has suggested, get them to pump it up, and wait for it to start dripping. As they added a dye, the puddle should show the colour. The puddle looks a bit red in the photo.

[Dee-C]

I thought the same.... well at-least big enough to be noticed?!

The coolant is bright red so it's a nice way of knowing where it's coming from.

I'll ask about getting it pressure tested this weekend and hopefully get it fixed.

Also @Geraldy212 you mentioned turning off the climate control in a previous post, When I do this it does slow the leak almost to a stop so I still believe it's something to do with the heater matrix etc.
I'm going to try refrain from using it until it's fixed.

Thanks again guys for your replies, I'll keep you posted.

[Dee-C]

Just a quick update, had the car this morning to be looked at and it turned out to be my water pump. It was only replaced like 6 months ago when I had the timing belt changed so it's covered under warranty, still need to wait 2 weeks for it to be replaced as the mechanic is on holiday. Just glad I know what it is and that it'll be fixed soon.

[Dee-C]

Sorry to revive this thread after a month but I'm still dealing with the coolant leak problem...

It's now become more severe and I'm losing coolant daily. The mechanic has since replaced the water pump but the leak returned the next day. He has now said it is the feeder pipes and that he has a feeling it could be due to bad pressure and ultimately a head gasket problem.

After arriving home today after picking the car back up from the garage I checked the coolant and it was at least double the amount that should be in the bottle... well over the max line and almost at the cap?!?! Would this not cause more problems with pressure as it now has no space to breath and will force the excess coolant out at the weakest point?

I've cut my loses with the current garage as it's almost 2 months wasted and still no repair. I've booked it in with an official Audi dealer next week and hopefully they don't come to the same conclusion...really don't fancy replacing the head gasket

Any help would be much appreciated.