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slow coolant leak. could it be a bad reservoir cap?

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Old 03-07-2006, 04:05 PM
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slow coolant leak. could it be a bad reservoir cap?
Old 03-07-2006, 04:10 PM
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is there a lot of crust around the cap? how slow is the leak?
Old 03-07-2006, 04:11 PM
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no crust around the cap at all. i'll notice it about 1" under the line maybe every 2-3 months.
Old 03-07-2006, 04:15 PM
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Default doesnt sound like it then. it shouldnt be too hard to find if you follow the coolant lines and look

for pink crust. mine was leaking from where it goes through the firewall next to the battery because the clamp had slipped off a bit. could also have something to do with the oil cooler iirc and that's a bigger problem but someone else would probably know more about this or you could search for more info. check around the engine compt. for pink crust and try to find where it's coming from.
Old 03-07-2006, 04:16 PM
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thanks for the info
Old 03-07-2006, 04:27 PM
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check around the oil filter for a leak. The oil cooler hoses typically end up leaking on 1.8Ts
Old 03-07-2006, 05:16 PM
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yeah the crust is the key... anywhere you see pinkish orangish crust is where its leaking
Old 03-07-2006, 06:27 PM
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Default the usual suspects are....

1. the coolant lines going into the oil cooler (above the oil filter). Those factory spring clamps almost always leak. Check this first.

2. the o-ring sealing the housing for the coolant temp sensor in the back of the head starts to leak. If so, you'll see dried crusty coolant droppings trailing down the back of the motor.

3. bad water pump. You'll see crust dripping down from the weep hole in the bottom of the pump.

4. blown oil cooler (though this will usually result in oil/coolant mixing which you'd probably have noticed by now).

Less likely causes:

1. cracked head gasket
2. cracked head
3. leaky radiator
4. leaky heater core

Good luck!

Cheers,
Old 03-07-2006, 08:21 PM
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Default I think I personally have #2

I noticed dried up coolant on the back of the engine (near the firewall, passenger side). Does this sound right? If so, how hard is it to fix?
Old 03-07-2006, 08:41 PM
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Default did you check your coolant flange (behind the engine) for crust? mine looks gross.

i'm gonna replace an o-ring or two and see if that fixes it. check out the tech article by BSK if you haven't already.


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