I can't replicate the issue and it doesn't happen hardly ever, but under a few circumstances I get the issue. The cruise light always stays on after the button is hit once and doesn't turn off, everything else works okay. Sometimes the light won't turn on and cruise won't work and nothing happens when the button is hit.

However here is the problem. If the light is on and the cruise is working but then later in the drive after the cruise is no longer engaged but light on, the light will shut off. If the cruise button is hit after that exact scenario the xj hiccups/stutters for a fraction of a second. Every time the button is hit and it has throttle it does this.

I remember it doing something like this in the past after cruise was on for the expressway and i was turning down my road. It would jerk 3 or 4 times in a row within under a second, kind of like a tranny issue.

I am thinking maybe the cruise control servo is bad and some how killing the vacuum? Not a big deal but just thought it was really odd what was happening.

 

Bump because I am still curious. Hasn't happened again.

 

You ever figure out what was going on with this? I'm having the same issue now. I never use my cruise control. However when I'm driving, usually right after starting up, my cruise control light will randomly turn on and my engine will start stuttering and cutting out and losing power. It will do that for a few minutes when I turn the steering wheel at times. But when the vehicle warms up it completely stops and runs great. So strange