The EchoTime DICOM field stores a value in milliseconds, but BIDS specifies it in seconds.
When ezBIDS reads NIfTI images + JSON sidecars, it multiplies the EchoTime by 1,000. This scaling should not be necessary since most tools producing the sidecars (e.g. dcm2niix) already convert from milliseconds to seconds. The scaling probably should be removed, as it results in an incorrect conversion for my data (in the below example, the JSON sidecar stores 0.004s, but after the conversion the result is 4s):
