When the accelerator pedal is release, clunk noise occurs while driving.
Car Problem Diagnosis
Clunk noise when the accelerator is release while driving happens because when the accelerator is release the stress on the transmission is reduced and if there is a part that is not secure such as the drive line joint, a clunk noise will occur while driving. When the drive line joint goes bad, it will create a noise.
Possible Cause of Clunk Noise When Accelerator Pedal is Release
Faulty drive line joints
All About car Recommendation
Bring the car to a reputable auto repair shop and ask the mechanic to inspect the drive line joints, for front wheel drive car it is called the CV-joints and for the rear wheel drive car it is called the U-joints. Depending if your car is a front wheel drive or rear wheel drive is what the mechanic will check. This kind of problem must be dealt at once to avoid a much bigger problem in the future.