Burning coolant(?) on turbo

[2018gti]

For a couple months I’ve been trying to figure out why I get the smell of a bakery/burning bread coming through the vents every time I come to a stop. I replaced the cabin filter, didn’t help at all. thought it was maybe something with the brakes heating up when coming to a stop. earlier I stopped at a light and the smoke smell was so strong I was getting concerned there was an actual fire under the hood!

I had sniffed around under the hood before but this time I looked a bit further under the turbo. and, wow:

is all that dried, burning coolant??

this area seems to be the culprit and I’m assuming it’s a leak from the plastic adaptor and/or the hose. I’ve seen posts about this part leaking but I was not prepared for the nasty creme brulée on what I’m guessing is the hottest part of the exhaust.

 

[DSC808]

Pretty common leak. It's a plastic piece that gets brittle. Replaced mine with a metal one from EMD No issues after. Maybe like a 30 minute job.

 

[2018gti]

when I was reading people’s posts on the issue a few months ago, I bought one of the metal EMD Auto ones just in case. which is ending up to be pretty convenient right now as it’s sitting on my desk. planning to do the swap soon and hopefully clean up all the burned residues on the turbo. I guess I’m lucky it didn’t all of a sudden let go but built up over a period of time.

 

[DSC808]

Take out the 2 torx screws, disconnect the top rubber clamp; pull out the adapter with the hose and replace.

 

[2018gti]

the culprit:

and new one in:

 

[berserker6]

You seeing that fizz around the adapter and the hose?

 

[2018gti]

Good eye lol, don't worry, I sprayed down the whole area with cleaner so it was still a bit soapy.

But, uh, that is the least of my problems right now just some advice for anyone who needs to make this fix. Get a replacement hose, also, unless your car is brand new or something.

The car was fine for 30 mins+ of driving gently until I decided to test it out by giving it some boost. Suddenly I started smelling coolant again and there was a lot of steam billowing out from under the hood. The hose now has a hairline crack in it. I'm currently trying to figure out the part number.. ‍ I must have bent/twisted it too much or something because my pick can't have reached the area where it split. ugh..

 

[BudgetPhoenix]

This just hit me too. Bought one of the metal ones. Didnt get a replacement hose though hoping I can get by.

 

[2018gti]

I guess you’ll know when you put it back together lol. I’m thinking now that mine may have been stressed first when the dealer installed a new turbo (not the most careful work judging from the scratches and not completely tightened downpipe), then me removing it again finally cracked it. was definitely annoying having to do the job twice - there’s a good chance you’ll be fine though I think.

in case it helps, the hose is 06K121051M and the 2 clamps are N90686701. also, have at least enough coolant to refill the expansion tank.

 

[BudgetPhoenix]

Whats funny is I bought the billet coolant adapter last week just as insurance before I even noticed this lol. I bought a little parts cleaner brush so I can get down in there and clean up all the oil crud with some degreaser and solvent too. I have 1L of premixed coolant already hopefully that is enough to refill what I lose but I have some more on order.

 

[Pineapple]

Good eye lol, don't worry, I sprayed down the whole area with cleaner so it was still a bit soapy.

But, uh, that is the least of my problems right now just some advice for anyone who needs to make this fix. Get a replacement hose, also, unless your car is brand new or something.

The car was fine for 30 mins+ of driving gently until I decided to test it out by giving it some boost. Suddenly I started smelling coolant again and there was a lot of steam billowing out from under the hood. The hose now has a hairline crack in it. I'm currently trying to figure out the part number.. ‍ I must have bent/twisted it too much or something because my pick can't have reached the area where it split. ugh..

Did you get a part number for that hose? Also a size for those torx screws? I have the aluminum adaptor in hand with clamp, but I don't have those two pieces.

 

[BudgetPhoenix]

Did you get a part number for that hose? Also a size for those torx screws? I have the aluminum adaptor in hand with clamp, but I don't have those two pieces.

in case it helps, the hose is 06K121051M and the 2 clamps are N90686701. also, have at least enough coolant to refill the expansion tank.

 

[2018gti]

@BudgetPhoenix that is exactly how mine looked, super dirty all around there. I tried the second time to keep the coolant from coming out but I think there’s no way, most of it comes out from the cylinder head. you can use that to your advantage in a way because it’ll carry away all the dirt you scrape off. 1L should be good but always good to have extra

let me be more generous with the details lol @Pineapple

Heat shield - three 5mm allen bolts and one 10mm nut. I took this off to get more access and make it easier to clean the area. one allen faces the firewall on the left and the other two are right around the adapter.

The screw that holds the coolant adapter to the head is a torx T30.

Pliers to move the hose clamps around.

Metal/plastic pick to get the hose off the coolant pipe. and to get the broken part of the adapter out of the head if it breaks off in there.

Paper towels/compressed air to get coolant out of the bolt holes for adapter, heat shield.

New parts as above: 06K121051M for the tube and (2) N90686701 for new hose clamps. and of course the new adapter. the clamps really were not necessary, I just wanted some shiny new ones. I had to reuse one of the old ones anyway because of course I dropped one of the new clamps down the engine bay and couldn't find it. also, the tube is not symmetrical vertically so make sure it’s flipped so that it doesn’t touch the valve actuators. you’ll know if it’s wrong because it won’t go all the way on the metal coolant pipe.

 

[BudgetPhoenix]

Just got it in the mail and did the job. Not too bad! I didnt remove the coil pack harness or anything just popped the top of the hose off and pulled the old one out with the lower still attached. Lost about a half liter of coolant and it all fell nicely into the drip pan. I did halfway pierce through the rubber of the hose with my L hook pick since it was stuck to the flange but it was at the very end of the hose so hopefully doesnt cause any issues... Really hope I just didnt jinx my self earlier lmao. At least its an easy enough job to do.

 

[2018gti]

glad to see it and glad it worked out. the aluminum piece looks so much better than the plastic one down there. yeah my tube split in multiple places in the middle of it so I think it was f’ed to begin with, I think yours will be fine