Lesabre Cruise

OK, somebody gimme an idea here please.  1993 Buick Lesabre, last year the cruise started acting funny.  Most of the time it would only set if i helped it by keeping my foot on the pedal.  Then it stopped altogether.  Now it's working again (about 75% of the time) and I don't even have to help it.   A few months ago I replaced most of the vacuum lines and did a vacuum check and couldn't find anything leaking.  In your opinion am I looking at something electrical or the vacuum?  If someone could narrow it down just that much, I'm open to replacing stuff one at a time till I fix it.  That's still cost effective.  I was thinking the VSS myself...  Thanks.

It could be the cruise control brake switch. There is a switch for the brake lights and one for the cruise control. The one for the cruise control disengages the the cruise electrically and by dumping the vacuum. The switch may be defective because you said you had to help the cruise by keeping your foot on the pedal. It may also be out of adjustment. You need to depress the brake pedal and push the switch towards the firewall. Then slowly pull the brake pedal backwards until it reaches it's resting position. There is a tiny plunger that sticks out the end of the switch which the brake pedal aloows to move in and out of the switch. The brake switch may also have dirty contacts inside and need replacing.sparky