If you experience difficulty starting the engine when cold, stalling at idle, or hesitations during acceleration, it may be the idle air bypass valve. This valve helps the vehicle idle steady when the accelerator pedal is not pressed.
Engine Stalling and/or Hesitation on Acceleration due to Faulty Idle Air Bypass Valve on Ford Thunderbird SC
Average mileage: 105,410 (68,230–125,000)
1 model year affected: 1990
4 people reported this problem
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when i put the car in drive and i am at a stop light or something were the car is not moving it idles to were there is a small viberation and i cannot figure out what it is motor mounts are fine i replaced the map sencor and the idle control sencor but still problem is accuring
When engine is cold, starts fine but when partially through warm-up cycle engine at idle lugs and stalls. no apparent reason for failure. RPM while shifting is erratic as well as base idle level is low.
Same problem here. Trouble starting, stalling out when idle directly after starting, and hesitation when accelerating. Replacing the idle air bypass valve fixed it all.