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 is there is a sudden loss of vacuum.

 

[Dtrain]

Thanks gmck, I will inspect those items
Dtrain