99 Taurus 24v DOHC, 90k miles. Had new plugs & wires yesterday and now the throttle won't release, take the car up to any speed take foot off the gas and car stays at that speed. When car is stopped at light the idle will suddenly drop from normal 750-800 rpm to almost zero then surge back up. I've looked at throttle return springs and all appears to be normal.
There does seem to be a slight whistleing sound comming from some place in the engine compartment that was not there before. Possibily a vacuum hose or manifold gasket leaking/sucking air? Any ideas what and or where the problem might be before I take it back on Monday to shop that did the job?
thanks for any heads up.