The participial phrase in the sentence The car parked in the driveway is leaking oil and making a mess is 'parked in the driveway'. Participial phrases begin either with a past or a present participle. Present participles contain an -ing. The -ings of this sentence are not part of a participle clause because they are part of the present continuous is leaking... making. Whereas, the past participle parked is the word that begins the participle clause.
