Well, Im not sure the P1595 code has much to do with the issue you are reporting.
If you have an idle issue and wont rev at full throttle, I would check the IAC and TPS. Clean your IAC, this is simple to do.
With the Key Off, remove the IAC and use spray carb/choke cleaner to clean all the carbon off, spray the intake port out as well.
let sit for several minutes to evaporate spray cleaner. Then lightly spray IAC with WD40 before instalation.
Bad TPS could affect your cruise control operation as well but I dont think it would cause this code.
4.0 I6, 265/75/16 Treadwright Claws, IRO adjustable track bar, 4" RCX short arm lift with Adjustable control arms all around.