Q: Car check engine light is off. Car accelerates by itself in drive from 0 to 60 miles an hour. Replaced aci, no codes on computer, 1999 Ford Taurus

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Car check engine light is off. Car accelerates by itself in drive ffrom 0 to 35 and higher sometimes miles an hour. Replaced aci, no codes on computer, throttle is closed when car accelerates to this speed. When idle bypass valve is unplugged the automatic Accelaration stops we replaced it because valve was stuck and it didn't fix the problem. Please help. We're at a standstill and it is very dangerous. When brake is applied the engine revs hard. When driving it doesn't going nearly as fast but still moving soley on its own. Came to a hard stop. We took the tires off and have it on jacks this is where the speedometer goes wild in drive as well as the rpm. Usually about 3000rpm. A In park and neutral it idles Nnormal no vacuum leaks and cruise control is also not the problem help please
My car has an automatic transmission.

Hello - your Taurus has a Recall (#98V204000) against the cruise control, which can cause unintended acceleration. In a related later issue, new Taurus models had problems with twisted accelerator cables - again, from the cruise control, which may have caused similar problems. I would check with your Ford dealer to be sure any relevant Recalls or Service Bulletins for your specific vehicle have been applied (Ford will need your VIN for this). Otherwise, i would disconnect the cruise control completely from the throttle to see if that helps resolve the issue. If not, I suspect the throttle position sensor needs to be checked out.

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