5th gen cruise control speed fluctuation

When I set the cruise control of my 2011 4Runner the speed starts jerking around and/or proceeds to go into full acceleration until I turn it off. No warning lights or dash notifications. Anyone else have this issue or ideas on the fix? Regular mechanic says take it to an electrical shop. Online research suggests replacing the module which is $1200.

 

^Which "module"?

 

Sounds like normal behavior if you’re going up hills. Toyota is cruise control algorithms are not the best.

 

Totally normal. lol Or not.....

With 5 gears and how cruise works with Toyota it tends to stick in a lower gear, especially hills. Try on flat highways, that is where cruse on our 4R's is designed to work.

 

What they all said. Here in Colorado, it really likes to hold the low gear and hang at like 3k plus RPMs. I don’t use it for the most part because of that. Would be my biggest complaint but it is what it is. My suggestion, lol, don’t use it.

 

This doesn't sound normal to me.

The speed will fluctuate a little bit. And, if you're driving faster, driving uphill, and/or into a headwind, it will downshift a lot. Sometimes it will downshift 2 gears if it's really struggling.

 

So I am referring to to flat open road conditions I should have said. I’ve had the vehicle since 2011 and used the cruise control for years with no issues. But now when I go to set it at say 70 mph, it starts jerking around immediately and then proceeds to downshift and accelerate like the pedal is pushed all the way down.if I go to show somebody that is with me the problem, Anyone in the car with me will look at me like wtf?! lol

 

If it's doing that on flat open roads you definitely have gremlins in the cruise control. I'm not sure who is qualified to check that out other than a Toyota service department...

 

Yeah, mines not doing that. It works well on flat area, it’s the hills it doesn’t like.

 

Mine is horrible. It is hyper sensitive and acts like it needs to downshift and accelerate if it drops 0.1MPH below set point. I barely use it because of this.

 

Head winds can cause it to fluctuate. Then add a slight grade? It can be maddening.

 

may be it is transmission. ?

 

Cruise control with throttle by wire vehicles is fairly simple, just the stalk going to the ECM.
- Look in the wiring diagram in the service manual. Check for continuity and short to ground between the cruise control stalk connector at the clock spring and the ECM. Move the steering wheel back and forth a few degrees while you check, in case the defect is in the clock spring.
- If no wiring defect found, replace the cruise control stalk.