'94 Bonneville SSE with L27. cruise just doesn't work. i replaced some rotten vacuum lines underhood but that still didn't fix anything. the linkage seems to be hooked up correctly. where else can i look? maybe a fuse? i'm totally new to these Bonnevilles (i've owned this car 2 days lol).

TIA

try using a brick stick it over your pedal

1)cheap
2)eaiser than going to mechanic to fix cruise control
3)brick solution compatable with all makes and models

Could be the brake switch has become misaligned. Sometimes I have to pull up on the brake pedal to make it work. Sometimes, the TC won't engage either. I need to readjust it, bu it involves laying on my back under the dash.

Have you checked the actual cruise switch? They can go bad as well.

I have the identical cruise control system.


I went thru hell figuring it out...first replaced all 4 lines.....the multifunction switch twice...then checked out the brake switch. It turned out to be the actuator.

Does it hold the speed at all?

check the top vaccum hose.


note my photo here. The green are the hoses that fail, the red is the actuator that failed on my 94.




We really need to know whether it tries to engage even a little bit...if it does even the slightest ammount try to hold a speed it is 98% a bad line somewhere you missed...there are many areas where a vaccum line could break.


If it does not try to engauge at all it may be a dead actuator or brake switch or multifunction switch.

yeah those are the vacuum lines i replaced today; well, besides the rubber elbow that attatches to the actuator. i replaced both of those short U-bend vacuum lines, the vacuum lines between the check valve and firewall, as well as the FPR vacuum line. the FPR line was so bad i can't believe the car ran like it did. the two short U-bend vacuum lines were so bad that while the engine was running they were completely collapsed shut from vacuum!

is there anyway i can test my CC actuator before i replace it? anything else i can test that would be free and/ or cheap?

thanks for the info!

btw, the cruise control doesn't work AT ALL. it doesn't even try to maintain speed even for a short time. i'll try pulling up on the brake pedal tomarrrow and see if it works. i had a brake switch go out on my Cutlass once and the brake lights would just stay on (and of course no cruise control...no TC lockup issues since i have a manual in that car). the brake lights work fine on my SSE....

And I thought I was the only one that had replaced a bunch of vacuum lines. Did mine when swapping the exhaust manifold. Noticed the ugly and took care of it.

Your brake booster hose failed? wow

Go to a local "U pull your own junk" parts yard.


match up the number on the actuator itself, I used one from a 95. Same number.


If you can get one for real cheap I would throw it in. I am not sure how you would test It. I just gave up and threw that part in and it worked great from then on. Usually the multifunction switch ($15 yard part) or the actuator as I refer to it as ($20 yard part)

Agreed, sounds like the control unit.

let me know what happens. I have the same exact problem. Does not work at all.