87 4kq coolant reservoir cap bad?

[Kneale Brownson]

I'm told all the Audi reservoirs take the same cap:  443 121 321.  Last two
I bought were $9 each.

At 11:16 PM 04/18/2003 -0700, auditude at cox.net wrote:
>Hey Cade,
>
>Once the cap pops, it has to be replaced.  It's like a fuse that way.  You
>should be able to
>get a new one anywhere, but especially at an import parts place.  I think
>it should be around
>$8 or so, but I could be wrong.  You may end up with a blue one, I don't
>know if there are
>different pressures, but if you spec one for the car you should be fine.
>
>I'm wondering if you had a different problem that caused it to boil over
>or whatever it is
>called.  Is the fan coming on like it should?