Coolant & Head Gasket Issues: Common Problems

Hello everyone,

'On my Passat TDI, 115 hp, manufactured in 1999, with 163,000 km on the odometer, the coolant level in the expansion tank fluctuates significantly.'
'Additionally, I'm also experiencing this gurgling sound in the heat exchanger inside the cabin when the engine is cold. However, I can't see any air bubbles in the reservoir.'
And also, there should be no oil in the coolant or water in the oil filler cap.

I have already tried using the forum search function.

Is this a clear indication of damage to the cylinder head gasket?
How much longer can I drive like this?

At 180,000 kilometers, the timing belt needs to be replaced again. Would it be cheaper to have both the timing belt and something else replaced at the same time?
I'm not brave enough to tackle the job myself, even though I've replaced seals on a Golf2 diesel before. However, that car had much less electrical wiring and water hoses.
What is the cost of a cylinder head replacement at VW?

I'm actually a bit disappointed that something broke down so early – I would have expected such things to fail after 250,000 kilometers.
I treated the engine like a raw egg when it was cold, imagining how gently I was handling it.
I've only had one broken mass airflow sensor (MAF sensor) so far.

Thank you in advance.
Michael

Okay, first of all, hello.

A similar topic is currently being discussed in a related thread. Additionally, there is a wealth of information available in this forum regarding damage to the cylinder head gasket, its causes, the resulting problems, and the symptoms. Again, please use the "search" function.
That's all for now.
Replacing both the timing belt and the water pump together definitely saves money, as the belt needs to be removed anyway when replacing the water pump. However, it's impossible to say from here how many kilometers you can drive with the new parts. Therefore, I certainly wouldn't wait 17,000 km. So, I would definitely get it done soon. It's not significantly more complicated than replacing it on a Golf II diesel. You don't have to remove much of the electrical components, and a couple of water hoses are no problem. Also, there are excellent technical articles in this forum that provide a lot of information about the engine. Furthermore, there are good books with helpful information. Since your car is not the "newest" model, it's also recommended to purchase a VAG Com with an adapter (available here in the forum, or on the owner's website).

Regarding VAG prices, I can't really comment, but I'm assuming you'll have to pay quite a bit if they replace the timing belt and head gasket for you.

Hello everyone,

I've also replaced the head gasket on my AFN engine before (see the thread I mentioned). I've successfully replaced head gaskets on an Audi 80, a BMW E30 (both gasoline engines), a Golf II diesel, an Audi 100 diesel, and a T3 diesel. However, the procedure on the TDI was definitely on a different scale, in terms of the need for specialized tools, the number of parts that had to be removed, and the dexterity required. A mechanic in the Krefeld area charges 400 euros net for replacing the head gasket on an AFN engine, including machining the head. I paid about 150 euros for the parts (screws, gasket, G12plus coolant, and an oil pressure line that simply couldn't be removed without damage). I haven't included the cost of decent Torx tools in that estimate.

Regards,
Thomas.

...and I thought that, with the Passat engine already installed (AJM model), there was enough space in the engine compartment (aside from the need for specialized/good tools). At least, it looks very spacious under the hood of my Passat.

Hello again, and thank you for the information.

I already have the repair manual by Etzold.
I'm already quite experienced with DIY and repairs.
What specialized tools do I need for a cylinder head gasket replacement?

Torx sockets in common sizes.
Timing gauge for camshaft.

Are there absolutely no electronic aids allowed?

Is it enough to just slightly lift the head, or does it need to be lowered completely?
Probably, some remnants of the old coating will remain, which will be easier to remove once it's completely gone.
Will he also be completely dismissed from Volkswagen?
A previous speaker mentioned something about a kind of guide on this page. Where?
Does the front of the engine need to be put in service position, or can the belt be removed from the camshaft pulley?

Thank you, Michael.

Okay, if you want to replace the timing belt (which I would definitely recommend), you'll need to access the service position. Additionally, you'll need the Hazet tool for the timing belt replacement (crankshaft lock/centering pin). I can't tell you exactly which wrenches you'll need for cylinder head removal, but Ezold should know. You don't really need any electronic tools. A VagCom and diagnostic connector might be useful later for checking everything, but they're not strictly necessary. Feel free to remove the entire cylinder head, since you're already replacing the timing belt, and it's definitely better for cleaning than trying to work in that sensitive area.
There are linked instructions available for the timing belt replacement, likely from Rainer himself. These instructions refer to VP engines, but I've also managed to do it on a PD engine without any Etzold tools. Also, I believe someone recently posted an experience report and photos about the timing belt replacement on a Passat TDI PD.

Good luck, and please let me know how it goes afterward. That would be great. Take your time; I've often worked on things late into the night, starting with "I'll just quickly..."

Okay, yes, the issue with the keys for the cylinder head replacement should be very clear beforehand... but I can't help with that, as I've never drilled so deeply into my engine before .

Hello,

For my A4, it was necessary to bring the front end to a service position. In plain terms: everything had to be disassembled.

'There were problems with the oil pressure line on the turbocharger. The fitting under the coupling nut should ideally have a flat side to allow it to be loosened, but there's no space for that. As a result, the pressure line sheared. Then there's the return line under the turbo: even with universal sockets, flexible extensions, and other tools, it's a real pain to access.'
Then, regarding the turbocharger's fittings connecting to the manifold: you'll need to chisel off the nuts!
Then I had problems with the plastic nipples that the vacuum hoses are attached to. They break off very easily, especially at low temperatures.

'The alignment pins and adjustment gauge can be relatively easily made yourself. A crankshaft locking tool is probably only needed when you want to replace the timing belt.'

That's what happened with my application! It took us about 8 hours for two people.

Have fun!