Sharp made a brief but tearful appearance in Wollongong Local Court on Wednesday where he did not apply for bail and it was formally refused after it was revealed his private lawyer was not available to attend the courthouse.

He will return to court on Thursday for a possible bail application to be made.

Sharp, 33, and his partner, 31, were arrested in the Illawarra on Tuesday before police uncovered a pipe bomb, drone and baton.

Police allege the pair were left aggrieved after a driver tooted their horn at the woman when she was driving in a Warrawong car park - near Port Kembla - on February 22.

The woman then allegedly followed the car, recorded the number plate and tried to file a complaint with police.

But police allege the couple then took matters into their own hands, with an online harassment and intimidation campaign including death threats.

The escalating campaign ultimately led to the placement of a "sophisticated" improvised explosive device under the victim's car in nearby Koonawarra on March 5.

The victim was not known to the offenders and the work done to identify them was "ingenious" and indicated a specific intent, Det Supt McLean said.

He said the car targeted in the bombing was not destroyed, but the blast had the potential to seriously injure or even kill a person.

On Tuesday afternoon, the man was charged with two counts of using a carriage service to threaten serious harm, two counts of stalk/intimidate, using a carriage service to threaten to kill, destroying or damaging property, placing an explosive in/near a vehicle, threatening a witness and two counts of possessing or using a prohibited weapon.

His partner is expected to face court on May 22 after she was granted strict conditional bail on two charges including stalking.

The Fixated Persons Investigations Unit - a specialist squad set up in 2017 to target potential would-be terrorists or lone actors - helped investigate the pair.

With AAP

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