Members with greater knowledge than mine will be along this evening to tell you about EGRs and chokes. I kept my smog intact because it was all working; plenty of owners chop it out and plug the EGR, though it's typically done with a plate, not a wad of epoxy.

Since my truck is virtually an '81 museum piece (as far as being UFW, or UnFutzed With), I've been thinking about doing a vac line photo series on my thread. I will do that tomorrow. It won't answer all questions for an 85, but it should help some. The GREAT thing about these engines is that there's almost nothing that can't be fixed, restored, redone, undone, etc.

Here's a couple more shots - the one on the right was taken last year, one of the few I can find with the air cleaner off. On the more recent (left) photo, the green arrow points to that choke connection.