I have a 1987 xj6 series 3 in good condition with 85,000 miles. Any idea of what it's worth?

 

Your "good" might be the next guy's "poor/fair" or even "mint".

An ultra, ultra mint condition example might bring $8000 if the right buyer came along. At the other end a non-running parts car might bring $200.

I'd guess $2500-$4000 for an average/decent/good example.

It's really hard to say.

Cheers
DD

 

I have a saved search on ebay. I keep a watch going and in the past few months 85-87's have been forsale 2k-9k without selling. sales have completed with a few that sold for far less than 2k but were in 'fair' shape overall.
1985-1987 jaguar xj6

Compare yours to this one that is ending in 10 minutes, I would guess it will sell for under 1k and be far cheaper a parts donor than being a few items from jaguar its self.(if they even stock the part)
http://cgi.ebay.com/ebaymotors/1986-...item3a62319b82

 

As a point of reference, I bought my car for 6k last July. It had an absolutely mint interior (sans the headliner which was sagging), paint and sheet metal were 95% clean (few small spots around the bottom of front/rear glass), and it started and ran fine. I have since replaced many things to create reliability like hoses, fuel lines, gas tanks, plugs/wires/distributor, etc.

I also found a semi-running parts car for $450. So I would say somewhere in between is where your car will be priced.