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Is this a manual transmission?
How have you tested the ABS, by locking up on sand or gravel?
OK- I would start out letting the car idle, and seeing if you can hear any air hissing sounds- start under the dash, it may be an issue with your brake booster, and you can usually hear it from under the dash when you depress the brake pedal. Then move to the engine bay and listen for any air hissing leaks while you move and manipulate vacuum hoses. Roughness at idle is almost always caused by an air leak, because intake manifold vacuum is so high at idle, and also because the amount of air needed is low, so any change to that is major.
Which sensors does it say are not working? That will keep the ABS from working at all, if it doesn't know what speed the wheels are going it can't tell which ones to pulse!