Slight coolant loss, coolant smell in cab

Lately I've noticed a slight coolant smell in the passenger compartment when I first start up my '98 jetta. Coolant is a little low, but still above the 'min' line. I would guess this is from a heater core that's starting to leak, but are there any other coolant leaks that I would be able to smell in the cab when I first start it up?
If it is the heater core, how hard is it to change a heater core on this car?

Most likely the heater core. Big job (time consuming) but not really all that hard.

You do need to evacuate the A/C system, as the entire HVAC case needs to come out, after the dashboard and knee brace have been removed.

oilhammer said:

Most likely the heater core. Big job (time consuming) but not really all that hard.

You do need to evacuate the A/C system, as the entire HVAC case needs to come out, after the dashboard and knee brace have been removed.

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I forget the year it changed, does a '98 come from the factory with R134, or do I have to break into my secret stash of R12?

Also, is there an easy way to verify that it's the heater core before I tear into it?

Ussually a heater core wont stink till it warms up, I leave ac side of box in but it's still a pita

rampage said:

I forget the year it changed, does a '98 come from the factory with R134, or do I have to break into my secret stash of R12?

Also, is there an easy way to verify that it's the heater core before I tear into it?

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VAG switched way back in '93.

dr.diesle said:

Ussually a heater core wont stink till it warms up, I leave ac side of box in but it's still a pita

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That's what I was thinking, seems kind of odd to notice this in the summer, and only a slight wiff of coolant smell at startup. I still wonder if it might be something else... The amount of coolant loss is so minimal I'm tempted just to ride it out until it gets worse and I can tell what the problem is. I have a different vehicle to go to work in if needed, so it's not like I'll get stranded and have to pull an all nighter or take it to the shop to get it fixed. (I'll just be stuck driving the 6.7L Cummins and working the first 3 hours of the day to pay for my fuel to get to work...)

Can't the shop put die in or something and tell me where it's leaking from? That might be worth the $75 or whatever they'd charge to do it...

It is common to get smell at first because as the coolant warms up, the core expands and seals the leaks at the end tank gaskets. Happens a lot.

Do not let it go, as they can (and often do) suddenly fail and come apart. Many older VAG cars were under a recall for this sort of thing. It has happened to my sister's '96 Jetta, pretty much without warning.

If you absolutely cannot or will not replace the core now, you can disconnect and bypass the core at the firewall by removing the two hoses and installing some sort of bypass loop.

Keep in mind there is ALWAYS hot coolant flowing through the heater core, there is no coolant valve on the A3 cars.

It is really not that bad of a job. Like I said, just time consuming.