Redline7g

The cruise control on my 91 Z has quit working. I've had the car 3 years and it has 23k miles. The cruise worked until last summer. I checked the fuse panel, where should I look next? What is the common failure?

Thanks,
Randy

VetteMed

It's commonly a flaw in the vaccum system, leading to or from the cruise servo which is located above the battery. The vacuum line should be checked for cuts or chafing, including under the dash where the hose connects to the brake switch.

Redline7g

Well I traced all the lines and even pulled one with the car running and the vaccum seems to be fine. What next?

TommyL

Mine on the 90 quite working a few years back.... turned out to be the speedo gear in the trans. That could be the first sign of the grear going south, then the speedo works intermitently and the car might even stall when you stop... the first sign was the cruise. Good Luck!

Goldcylon

Been working around the pedals? Check the brake switches that they are centered on the full area above travel of the pedal arm. If they are off centered the cruise wont engage. Also if either of these switches are not working. GC

92 ZR1

Check the adjustment of the brake pedal vacuum switch. I had to re-adjust my 91 a couple of years ago.

Redline7g

I did have to replace the brake switch last year. I don't know if that's when it quit because I don't use the cruise unless we're on an interstate trip. What do you mean by "off centered"?

Redline7g

Thanks I'll try to check that too. Always fun to try work under the dash!

Goldcylon

It (the switch) needs to be centered on the pedal arm. If its offset it wont make contact with the switch and the cruise will not set.

Redline7g

After checking the to make sure the swithes were centered and making sure they were making contact, took it out for a test drive and the cruise is working again. Thanks to everyone for their input.

Thanks again,
Randy

Goldcylon