Cruise Control on 89 TBI Suburban

[Whiskey Junior]

I have been slowy refurbishing my 89 Suburban, and I have finally gotten to the cruise control. My cruise vaccum servo is broken, and I will need to source a new one. I am also missing the cruise control actuator rod, that links the servo to the throttle body of the injection system. I am going to try and repair the servo, the tab that links the servo to the rod has broken open, I might be able to braze it back shut, but I want to be sure I am in the right ballpark of size/shape etc when I am done.

Does anyone have good pictures they could share of the cruise control fittings on the 88-91 TBI Suburban/Blazer? Anone possibly have some old stuff they could share or sell?

 

[Vbb199]

I can take a pic of mine on my 89 burb later if you'd like.

Mine was also broken open, for what little it pulls, I just bent the opening closed.

As far as the actual cruise control diaphragm, when I was searching for one, they were all over ebay

 

[gmbellew]

pictures of my 1990 Suburban. I suspect they are nearly identical

 

[Whiskey Junior]

Thank you both so much!!!

 

[Whiskey Junior]

I just got the system installed, and it works (mostly)!

I have the “set” and “decel”, but “resume” and “accel” aren’t working. I know it’s probably the stalk, but I haven’t gotten under the dash to probe for voltage on the yellow wire yet.

That servo was awful to install.

 

[Whiskey Junior]

I replaced the stalk and the full system works.

I had been watching a ton of videos on this, but I couldn’t get the cable end to pass down the steering column, as the Doorman replacement is “fatter” than the original. I ended up simply sectioning the cable and resoldering after install.

Works like a champ now!

 

[mcarlo86]

I replaced the stalk and the full system works.

I had been watching a ton of videos on this, but I couldn’t get the cable end to pass down the steering column, as the Doorman replacement is “fatter” than the original. I ended up simply sectioning the cable and resoldering after install.

Works like a champ now!

The cruise on our '90 suburban doesn't work. Everything is still there, so I'm not sure where to start to try and diagnose what is wrong. I suspect the switch on the turn signal stalk could be part of the problem as the wiper switch is kind of finicky and the delay wipers only work when they want to. Any good videos you watched that were helpful?

 

[gmbellew]

The cruise on our '90 suburban doesn't work. Everything is still there, so I'm not sure where to start to try and diagnose what is wrong. I suspect the switch on the turn signal stalk could be part of the problem as the wiper switch is kind of finicky and the delay wipers only work when they want to. Any good videos you watched that were helpful?

The stalk is an easy and cheap fix to try. It only actually controls the cruise. The multifunction portion for the wipers just controls the wiper switch that is in the column.

Other portions of the cruise are a module under the dash and the servo under the hood. I'd start with the stalk and go from there.....

 

[Matt69olds]

Find the 4 pin connector for the cruise switch. It’s usually clipped to the steering column brace near the dimmer switch.

I don’t remember the colors or function, but it’s easy to test. One wire will show power anytime the ignition is on, assuming the cruise harness is plugged into the fuse box. Once you have verified the cruise lever has power, another wire will show power either the cruise switch turned on, it should show no power with it off. Another wire will show power when the “set” button is pushed, and another wire will show power whenever the “resume” button is pushed.

 

[Matt69olds]

I forgot there was a sticky on this subject.

Cruise Control Troubleshooting and Info

Long story short, I bought a simple lock up kit since my truck didn't have the system installed outside of the transmission. I replaced the wiring inside the transmission (Solenoid and pressure switch to the 4 terminal connector on the top... .it's a 700R4 btw). I ran the wiring up and through...

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