possibly stupid question

This might be somewhat simple a question, but there have been worse. I have a 93 XJ, and I get SOME spark knock (in addition to the other problems that I have thus posted here on this board) when the engine is under load, like in the 2-3 grand range. Does a 93 have a spark knock sensor? Also, I don't seem to have any sort of an EGR valve, and I just don't know why. I have seen other XJs and they have the EGR just below the TBI unit on the side of the intake, but mine just has a tube to the canister on the firewall. So, where's my EGR? Also, is the fitting at the siad canister supposed to have some sort of a baffle system to it? Because I pulled the tube off the fitting, and it hissed (vacuum FROM the intake) but I pulled the fitting itself off of the canister and that too hissed, leading me to believe that the fitting is regulating how much vacuum the intake can draw, is that correct? I could be way out in left field, an I probably am...hey, I've never owned a 4.0 before, only a feeble but faithful 2.8!

Thanks

No knock sensor. Chrysler eliminated it to save 15 cents per vehicle. Also no EGR -- they supposedly changed the cam specs to let the cam timing handle that function, but the cam specs in the FSMs apparently aren't accurate, so who knows?

In any event -- you can stop looking, 'cause you're not gonna find 'em on your XJ.

timing chain maybe?

Could, then, my mild knock problem be related to a worn timing chain? Also, there are a number of vacuum lines that go to the intake manifold, and all of them are under negative pressure. Well, the back one has a fitting (I think that I mentioned this before) with some sort of a baffle in it, and it seems a little clogged, because it sometimes can be blown through both ways, and sometimes it can't be, depending on how much you shake it around. This is not the line that I mentioned in my last post. This line goes to that tank (can't remember the name) on the passenger side of the car. The only reason I bring it up is because I am beginning to see just how sensitive the vacuum and emission systems are on these things. I just want to be sure that all of my vacuum lines are operating properly, so that I can rule out that possiblity in regards to my spark knock AND my oil burning. So, are all of those lines being vacuumed by the intake? or are some supposed to be free-flowing? or what?