[Prestonj]

I’ve just recently got this car handed down to me by my parents. It has been leaking a lot recently and we don’t know why. My dad said there once was a small leak on the hose connect to the top of the coolant reservoir he replaced it. That was to his knowledge the most recent and only leak we’ve had. I ran it today for about 10 min and there was a big puddle underneath. And another thing on the way home the coolant light came on. i was only about a minute away from home so i drove it home and i opened my hood and it was smoking on the left side kinda around the cylinder head. I’m new to cars so i apologize if my explanation isn’t the best. But I’m just wondering if anyone could help me pin down why it’s leaking

 

[Iowegian]

First of all, don't drive it with low coolant or you will soon be replacing the engine or the head(s).

What type of engine do you have (1.8t or V6)? Either engine has its own unique typical places for it to leak so knowing which engine you have is key. But please, don't drive it before you fix the leak.

I just saw the title says GLS. I think that means it's a 1.8t but I'll let those more knowledgeable chime in.

 

[PZ]

It looks like a 1.8T with the cat next to the exhaust manifold. If so, I expect the coolant flange is failing. There is a writeup in the Info Forum.

 

[Prestonj]

It looks like a 1.8T with the cat next to the exhaust manifold. If so, I expect the coolant flange is failing. There is a writeup in the Info Forum.

Could you send me the write up i don’t think i can find it.

 

[AndreasPassat]

Doesn't anyone know how to use the search function anymore?

 

[PZ]

You will need to confirm if it's the flange or just the temp sensor seal. The flange is pain to replace.

DIY: Beginner’s guide to B5/B5.5 1.8T Coolant Flange...

Standard disclaimer applies. Post for information only. Repair your Passat at your own risk Symptom: =========== Coolant flange is made of plastic. It locate at the back of engine and can be felt but not seen. It has (a) CTS (coolant temperature sensor) on top (b) connected to engine block on...

www.passatworld.com

 

[Prestonj]

I’ve just recently got this car handed down to me by my parents. It has been leaking a lot recently and we don’t know why. My dad said there once was a small leak on the hose connect to the top of the coolant reservoir he replaced it. That was to his knowledge the most recent and only leak we’ve had. I ran it today for about 10 min and there was a big puddle underneath. And another thing on the way home the coolant light came on. i was only about a minute away from home so i drove it home and i opened my hood and it was smoking on the left side kinda around the cylinder head. I’m new to cars so i apologize if my explanation isn’t the best. But I’m just wondering if anyone could help me pin down why it’s leaking View attachment 107116
View attachment 107117
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I found out it’s leaking from the thermostat housing

 

[VAGguy]

That's a pretty easy one to do. Just remove the intake hose and you should be able to get to it without too much trouble. I recommend a new housing and new thermostat while you are in it.

You'll need to drain most of the coolant to do it. There is a drain at the bottom of the radiator next to the driver side fog light. Just pull off the fog light grill and it is behind the rubber flap towards the center.

 

[graham.tillotson]

Not sure if this is the same setup as my car (2001 Passat 1.8T) but I just changed the thermostat and o-ring. Top hex bolt was pretty easy but the lower one was a bear. Ended up using a long T-handle allen wrench and getting leverage with a screwdriver run through the handle. Almost no space near that lower bolt so I had to get at it from further out.

Graham

 

[PZ]

Just a reminder, if you are messing with the thermostat bolts on a 1.8T, disconnect the battery. It's a hell of a spark if you don't.

 

[graham.tillotson]

Just a reminder, if you are messing with the thermostat bolts on a 1.8T, disconnect the battery. It's a hell of a spark if you don't.

Ha! +1 for that tip. I can 100% confirm it is a hell of a spark. Lesson learned!

Graham