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ABS out of control

VR38

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I think one of my ABS hubs are damaged and when I push the accelerator to the floor and then try to stand on the brakes the car just keeps accelerating.
It will not do this if I do the reverse and if I brake normal (without my foot on the accelerator) then the ABS works normal.
 

VR38

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I think one of my ABS hubs are damaged and when I push the accelerator to the floor and then try to stand on the brakes the car just keeps accelerating.
...and the pedal goes hard, when I stop accelerating the brakes return to normal.

Does your car do this too?
 

hako

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If there is a fault with the ABS you will have the ABS warning light on - if not then your ABS is OK. Accelerator and brakes on at the same time is generally only used to check the stall speed of the torque converter - do it for more than 5 seconds and you cook the oil and can/will damage the converter - engine revs should not go higher than whatever stall speed your converter is - my old Jag was 1900rpm...not sure with a Commo.
 

VR38

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If there is a fault with the ABS you will have the ABS warning light on - if not then your ABS is OK.
I think it is the HUB, not the control module.

Accelerator and brakes on at the same time is generally only used to check the stall speed of the torque converter - do it for more than 5 seconds and you cook the oil and can/will damage the converter - engine revs should not go higher than whatever stall speed your converter is - my old Jag was 1900rpm...not sure with a Commo.
I can accelerate way over 100km/h, the brake pedal just goes hard till I lift off the accelerator pedal so no brake strain on the motor/box.
 

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I think it is the HUB, not the control module.

If you think the ABS hub is faulty the ABS control module will log a fault and turn the ABS warning light on.

I can accelerate way over 100km/h, the brake pedal just goes hard till I lift off the accelerator pedal so no brake strain on the motor/box.
Not quite sure what you are saying here....what exactly do you mean by "the brake pedal just goes hard"?
 

_R_J_K_

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the brake pedal just goes hard till I lift off the accelerator pedal so no brake strain on the motor/box.
...and the pedal goes hard, when I stop accelerating the brakes return to normal.
I think one of my ABS hubs are damaged and when I push the accelerator to the floor and then try to stand on the brakes the car just keeps accelerating.
It will not do this if I do the reverse and if I brake normal (without my foot on the accelerator) then the ABS works normal.
Those sentances make it sound like you are trying to press the brake and the accelerator at the same time. Is that what you are doing?
 

VR38

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Yes, Accelerator pedal and then the brake pedal, in that order, at the same time.

If I press the brake pedal and then the accelerator pedal in that order at the same time then everything is normal.
 

immortality

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sounds like you have a vacuum problem. when the car is idling the engine produces a high vaccum and this works to assist you (through the brake booster) the brake booster has a one way fitting so that when you accelerate the vacuum is maintained in the brake booster. if the pedal feels really solid when your accelerating (very little engine vacuum) i'd suggest that your one way valve is stuffed.

try the brake pedal with the engine off. then start the engine with your foot on the brake pedal and see what it does. then switch the egine off again ( still with your foot on the pedal) and tell us what the brake pedal does
 

VR38

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Pedal sinks then when off then it tries to push back at me a bit.
When I switch the motor back on and drive off there is a small, almost electric motor type noise from under the bonnet/
 

immortality

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either your one way valve is stuffed or the booster has a leak.
 
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