After some spirited turbo-glowing mountain driving I developed a coolant leak. I was stumped at first as it looked like I was leaking from the coolant flange which I replaced a couple years ago. I've heard of them cracking under high heat but I didn't think a new one would give way this quickly.

After a couple more days of head scratching I did some more poking today and saw that the heater core inlet hose is now cracked at the flange connection.

Has anyone had to replace this hose before? Any tips or advice? I haven't been able to find much info online yet.

I'm sure removing the coolant flange would make it easier (may very well be necessary.) Should I go ahead and replace the flange and all o rings while I'm down there? I replaced the ECT last time as well, so I don't think I'll bother with a new one this time around. Can save me $30.

 

No one huh?

I found out a little more info. Looks like I don't have to remove the coolant flange to get at that hose, so that saves me a lot of time.

A new hose is about $90 from my local shop or most places online. However I found one place that has them for $11.

$11.00 8D0819371H New Supply Hose for Heater for 98-05 Passat 1.8T, 96-02 Audi A4 1.8T.

If it sounds too good to be true it usually is, but the hose looks legit. I think I might order it and have my local shop examine it. If they say it's ****, oh well, I'm out $11. But if the hose is legit, then I can save $80.

 

Hello Lukas, I am having the same problem in my 1998 A4 1.8. Sounds to be exact actually. Anyways, I am also trying to learn more about it. Did you end up fixing it? If so, how easy was it? Also, was that hose for $11 legit? I am considering getting it from that same place. Looks to be Parts for VW Jetta TDI Golf Passat 1.8T Beetle Eos Audi A4 TT A3 A6 5000 4000 100 200 Cars Diesel Injector Pumps, which seems legit. Please let me know, thanks!

-Alek

 

It turns out it was my coolant flange the whole time. I spent $90 and replaced the hose for nothin'! Oh well..

But yeah, make sure that is where your leak is coming from before you spend the money replacing the inlet. The coolant flange is a much more likely suspect.

 

I am very glad I asked. I actually went out after my last post, took off that whole hose, inspected it thoroughly, and saw nothing wrong with it. So I was pretty confused, I knew the leak was right there, I figured it was the plastic piece connected to the hose, but the flange makes a lot more sense! And mine looks like crap! So thank you for your help, I will definitely be replacing that.