The ignition coil inside the distributor can fail. There will be a hesitation on acceleration, especially when the vehicle is warming up on cold, rainy days. The pickup coil inside the distributor can also fail and cause a no-start condition. There have also been some failures of the radio noise suppressor inside the distributor, which can short out. Our technicians recommend replacing the whole distributor with a complete, genuine Toyota distributor if any of its components fail.