dhuff

I have a 2013 S, 4.8 V8, and have always noticed a slight smell of coolant after a long trip since buying it in 2020. Yesterday I used the car to move our camper around, a long backing-up on a sloped driveway, so a pretty good workout. The smell was strong and some white smoke was coming out of the right exhaust pipe. The car was warmed up from use prior to the move.

Bought it with 71k miles and now has 115k, and it’s been a great tow vehicle for the camper here in the hills of SW Virginia. No noticeable change in performance, have had to top off the coolant twice in 3 years.

Is it head gasket time?

leftlane

I had a small coolant leak in the Y pipe under the intake manifold - didn’t notice until I started to see some coolant on the ground. Have you seen any drops anywhere?

RAudi Driver

If you're thinking the coolant is running through the engine, then it could be head gasket but I have yet to hear of a member who's had to replace one. The white smoke out of the right exhaust, did it smell? Was it constant and is it still doing it? Did it do it when the vehicle was totally warmed up or was the engine cold? What's the weather like where you are at?

Another path for coolant to enter the engine is through the oil cooler, however, I've never heard of another member having to change that out either. They've only changed the O rings to prevent the oil from leaking out on to the belly pan/ground. It could happen but I've yet to see it. You can pull that cooler off and pressure test it and it looks like it's easy to get to. You'll have to drain your oil to do it.

figure1a

I have had that slight coolant smell on my 2013 TT for 10 years. Porsche has never been able to smell it when I take it in for service. I am never low on coolant. A mystery for me.

The white smoke, that I have never see.

dhuff

No, no signs of leaks. I’m familiar with that issue so I’ve kept an eye on that.

dhuff

I just saw the smoke for a minute, looked like what you see on a cold morning, but it was a warm dry day and the car was just back from a 30 mile round trip to town. I could smell it all around as I disconnected the trailer. I haven’t seen it since.It’s encouraging that you’ve never heard of a head gasket replacement, but the symptoms… Another chronic problem I’ve had, just about ever since we bought it, is an occasional CEL for the right pre-cat O2 sensor output voltage. I replaced it but the same code comes back every once in a while, usually during harder driving. I’ve heard that coolant in the exhaust can cause that. I also noticed that the cat clamp on the right side is an Audi clamp and a bolt was missing from the mounting flange, so it seems that work was done in this area before. No carfax mention and I don’t know the previous owner.

twodollardoug

Three things to check for a blown head gasket. First, open the coolant reservoir and see if it has an exhaust smell to it. Also, check the engine oil. It will have a chocolate milkshake appearnce. Also look at the oil filter, it will have wavy pleats if coolant has passed thru it.

RAudi Driver

You Milkshake will bring all the mechanics to the shop. Don't let that happen.

Whitegalaxie

I really doubt a head gasket issue. Much more likely to be either the plastic or Aluminum coolant pipes under the intake or the ones at the back of the engine or the ones going to the T-Stat or one of the T stat seals.There are loads of places to leak and all are a simple to fix bar a bit of time and money. Pressure test the system and see if that gives you any clues. If not, then at the mileage you are it it is probably worth doing some PM maintenance on the cooling system and you will uncover it that way.

dhuff

I do all my own work, so no worries there! Problem is, I’m just getting started building my dream garage and workshop, pour the slab next week. Hope it doesn’t get any worse until I get it built and the lift installed.

RAudi Driver

I drove with my leak for quite some time.

dhuff

Hope you’re right, it’s the white exhaust coming from a warmed-up car on a warm day that has me worried. I’m a former fighter jet crew chief so I’ve got some experience searching for leaks but so far, nothing. I’ve recently purchased every fluid needed and will be spending some quality time with it soon, maybe as you say, something will show up.

twodollardoug

Wow... White smoke on a warm engine. Does it smell like exhaust in the reservoir?

dhuff

I saw a waft of smoke, probably actually steam, for a second or two after backing our 3500 lb camper about 100 ft up a bit of a grade, could see it in the back-up camera when I stopped. Haven’t seen it since. Reservoir didn’t exactly smell like exhaust, but not totally like antifreeze either, almost like a fried circuit board. We’re going on a 600 mile trip this weekend so I’ll do a couple more sniff tests and keep an eye on the fluid level.

twodollardoug

Cool, keep us in the loop.