cruise control problem

[Randy Hagins]

I had my '86 GN out tonight on the highway and went to use the cruise control. When I pushed switch over to the right the car felt like it was going WOT! I turned off the cruise control then tried it again, same result. I did this 2 more times with the car wanting to go wide open. This was working 2 weeks ago. The stalk was changed out in 2008 and I did change out power master accumulator 3 weeks ago. Not sure if that has anything to do with it. Has any one heard of this problem? If so please direct me on where to look to correct it. Never expected to have a problem with the cruise control. Thank you very much in advance!

 

[Black Car]

If the VSS buffer is acting up or going bad, it could cause this problem.
If you or a freind has direct scan you can check to see waht the buufer is showing for speed. You will have to record soem than play back frame by frame to see if the speed is jumping all over the place or just not reading at all.
scan master will not work.

There maybe other things such as bad diaphragm or cracked hose goint to the diaphragm.

Gary

 

[Rich Gio]

If the VSS buffer is acting up or going bad, it scan master will not work.


Gary

I'm having the same problem, but speed reads fine on my Scan master. Why do you need to read it on direct scan?

 

[Black Car]

The scan master will not read as fast as direct scan. DS is up to 18 frames per second. My SM was showing steady speed just like the speedometer.

One day, my car acted up and I had the DS connected and the slight '"miss" happened. After reviewing the record of what was going on, I found my 2 year old problem.

My buffer was showing a different speed every frame and it was anywhere from 5 mph to 200mph, mostly in the 30-100 mph range.
My ghost was a very slight "miss", which turned out to be any speed over 180 mph for the fuel shut off.
This also caused my cruise control to either do nothing or peddle to the metal, all depending on the instant that I selected my speed.

 

[Rich Gio]

The scan master will not read as fast as direct scan. DS is up to 18 frames per second. My SM was showing steady speed just like the speedometer.

...but if you have a powerlogger installed with the new chip in the scanmaster it reads faster than direct scan (25 frames per sec VS 18 frames per second for the direct scan)

 

[HighMileage]

I had my '86 GN out tonight on the highway and went to use the cruise control. When I pushed switch over to the right the car felt like it was going WOT! I turned off the cruise control then tried it again, same result. I did this 2 more times with the car wanting to go wide open. This was working 2 weeks ago. The stalk was changed out in 2008 and I did change out power master accumulator 3 weeks ago. Not sure if that has anything to do with it. Has any one heard of this problem? If so please direct me on where to look to correct it. Never expected to have a problem with the cruise control. Thank you very much in advance!

What if you use just the Set button on the end if the stalk to set the speed?

I've got a '90 Olds Ciera with 3300 that is doing the same thing you are describing. As long as I don't use the Resume/Accel switch to set or resume speed,and just use the Set button,the Cruise holds without incident. If I do use the Accel/Resume,it goes wot.

Recently,my '87 GN's cruise wouldn't work. The light would come on,but no Cruise. I took the servo off the car mentioned above,and put it on the GN. It now has perfect Cruise. So rule out a bad servo causing your issue. A j/y servo was put on the Ciera. The wot issue remains.

There is a cruise module under the dash near the gas pedal. It takes minutes to change if the lower panel is off. My GN has one off a 307 equipped '87 Regal. It was installed to try and diagnose the old issue.

Maybe the module is the wot issue you and my Olds is having? Easy to change,and cheap.

I hope this helped somewhat.

Steve. '87 GN,t-tops.