can anyone tell me where that vacuum line connection just to the right of the hose in this picture goes?
I found a diagram online that says accessory, but that is not very specific

thanks in advance

A soft EVAP hose connects to there, then if you are standing at the front of the car, look left and there is a wiring harness, it should have wires for the injectors, and what not coming out of it, there should be a hard plastic T in it that goes inside the car around the passenger door area, that provides vacuum for the HVAC to switch from vent, to defrost, to floor.
The other part of that T runs inside the wiring harness till it gets near the front of the car near the battery area, then it comes out and runs underneath the bumper area, then it makes its way to the EVAP canister which is under the airbox/PCM..

I can try to get some pics for you ASAP if needed, I had to replace all of those soft EVAP hoses and connectors not too long ago, they were all dry-rotted.

Was thinking it over, your EVAP system may be a tad different in the routing than my 96', but the hose should still go where I said it goes, it may just run a slightly different path.
I think the newr models with the 3800 II had the EVAP canister closer to the driver side firewall area, not all the way at the firewall, but kind of in the middle..

I'm guessing it might go nowhere, might just be capped......that did feed the vac actuators in the HVAC system, on the older models.....but a 2003 uses electrical actuators rather than vacuum....

That explains why I see some pictures with them capped. Good to know Tech II.
What year did GM stop using vacuum activated actuators?

I think 1999 was last year for vac actuators in a LeSabre....

This comment is for anyone looking around on here that may be pulling the fuel injectors out, as in Kenneth'* photo. Very good idea to get all that crud away BEFORE you disassemble. Looking at that photo made me nervous, seeing the potential for gritty crud getting into the intake areas inside the manifold. Much better to clean the areas like that before getting into the actual work.