Why does my cruise control turn off on some hills?
#1
Why does my cruise control turn off on some hills?
Today I took a road trip and ran into my 4runner jumping out of cruise three times on me. All while going up hills. Does the cruise have a kick off point?
#2
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The truck's on-board computer will turn the cruise off when it senses the throttle near wide open. While going uphill, the cruise control will be adding throttle to maintain the speed you have set. When the computer sees the signal from the throttle position sensor go to near wide open it will disengage the cruise control as a safety precaution.
If the problem occurs on smaller hills the truck may be suffering from a lack of power or performance.
If the problem occurs on smaller hills the truck may be suffering from a lack of power or performance.
#3
You may be able to improve the situation by installing a vacuum check valve and accumulator between the cruise control motor and the engine.
The cruise control motor or acuator operates off vacuum normally, and is usually connected directly to manifold vacuum. So as you go up a hill and need more throttle, manifold vacuum goes down, making it impossible for the cruise control to open the throttle fully.
Installing a vacuum check valve keeps the vacuum high at the cruise control motor. An accumulator inline between the check valve and the cruise control motor helps ensure sufficient quantity of vacuum to fully open the throttle.
The cruise control motor or acuator operates off vacuum normally, and is usually connected directly to manifold vacuum. So as you go up a hill and need more throttle, manifold vacuum goes down, making it impossible for the cruise control to open the throttle fully.
Installing a vacuum check valve keeps the vacuum high at the cruise control motor. An accumulator inline between the check valve and the cruise control motor helps ensure sufficient quantity of vacuum to fully open the throttle.
#6
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Mine does the same thing. It does it when I would normally downshift. Now I just anticipate those hills and then put it back into cruise control after I climb it. Our trucks are way too slow
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