No belt - it's a chain. Service longevity has been reported at 250Kmiles or better - I only changed the chain in my 87 because I was that far into the engine anyway...
Coils should only be replaced due to failure. I don't know how long the packs will last - I think I have a 1999+FSM somewhere, so I'll look for the test when I get a chance (could be sometime in the next month - they're in a box in the garage somewhere...)
Apart from that, there isn't too much for you to worry about. Keep your fluids clean, and you've done most of what you need to do. OBD-II Code Readers can be had for $200-400, if you plan on keeping this XJ for a while one would be a good investment.
No belt - it's a chain. Service longevity has been reported at 250Kmiles or better - I only changed the chain in my 87 because I was that far into the engine anyway...
Coils should only be replaced due to failure. I don't know how long the packs will last - I think I have a 1999+FSM somewhere, so I'll look for the test when I get a chance (could be sometime in the next month - they're in a box in the garage somewhere...)
Apart from that, there isn't too much for you to worry about. Keep your fluids clean, and you've done most of what you need to do. OBD-II Code Readers can be had for $200-400, if you plan on keeping this XJ for a while one would be a good investment.
Good call with the code reader, that thing is very convenient. I just got one for my Jeep from JeepersandCreepers and I love it. Ironically, my check engine light came on the very day that I recieved my code reader in the mail but I was able to diagnose the problem in less than a minute and the problem was fixed in a couple of hours versus taking it to the dealer for possibly days.
but I was able to diagnose the problem in less than a minute and the problem was fixed in a couple of hours versus taking it to the dealer for possibly days. 
