Intermittent cruise control

[Dtrain]

I was having a problem with the cruise on my 91 burb squarebody , it works fine but cuts out , then I press the resume button and it works again. I installed the cruise (original stock parts) in this wagon about ten years ago and it worked flawlessly until now. Not sure if it's a vacuum leak or a ground problem, any ideas would be appreciated.

 

[75gmck25]

I would start by checking the wires for chafing or breaks. The controller relies on a reliable signal from the speed sensor on speedometer cable (or in a '91 maybe it comes from the ECU), and it might be dropping out the speed signal. The other place to check is all the vacuum connections, especially the line going through the firewall to the brake pedal. It shuts the cruise off if there is a sudden loss of vacuum.

 

[Dtrain]

Thanks gmck, I will inspect those items
Dtrain

 

[Matt69olds]

Find the cruise control lever connector at the base of the steering column. It has 4 wires with a white connector, with the matching connector most likely clipped to the column mounting brackets.

One of the 4 wires is ignition feed, it should have power anytime the ignition is on. There is another wire that has power only with cruise power switch turned on. Then another wire that’s powered when the “set” button is pushed, and the last is powered when the resume is pushed.

One at a time, put a test light on each terminal and verify it functions as expected. Then with the test light wedged in the connector, move the turn signal lever thru its range of motion. Bang on the column, move the tilt wheel (if equipped) the gearshift, and closely observe the light. If it flickers or acts strange, then you just confirmed there is an intermittent break in those tiny wires.

If that’s too much work, start with a replacement cruise lever. last time I bought one it was about 35 bucks. More than likely that’s your issue, those tiny wires can only bend so many Times before they break.