The man accused of transporting pipe bombs along the Sturt Highway pled guilty and did not apply for bail at a recent court appearance.

33-year-old Timacoy Jason Williams remains in custody after pleading guilty to all charges at his October 4 appearance at Griffith Local Court.

Appearing via video link, Williams faced two charges of possess explosive device in public place, two charges of prohibited drug and one charge of custody of knife in public place.

The charges relate to the discovery of two suspected pipe bombs in a vehicle stopped on the Sturt Highway near Hay on September 30.

The discovery resulted in 50 kilometres of the highway being closed for eight hours between Hay and Maude, while police investigated.

The court heard Williams acted suspiciously during a routine traffic stop, where he was the passenger in the vehicle.

Police said officers could smell cannabis in the vehicle and said Williams was not wearing his seatbelt correctly.

When asked for his ID, an agitated Williams gave a false name.

The driver produced a positive drug test on the roadside, leading Police to further search the vehicle.

Officers searched the car and found a black sports bag in the passenger side footwell, which contained cannabis and two silver metal cylinders with fuses which officers identified as pipe bombs.

A jewellery box and a satchel bag containing a wallet with Williams' true name on it were also found.

The box and bag were searched and police found cannabis and a clear resealable bag containing a crystal substance believed to be methamphetamine.

A 29.5-centimetre knife was also found under the passenger seat.

Police also found other items including a 'Mongrels' outlaw motorcycle gang vest, a black ski mask and black tactical gloves.

The court heard Williams has ties to bikie gangs and had what was referred to as an “extensive criminal history.”

The magistrate adjourned the matter for sentencing on November 30.