Whispers, sackings and party disquiet have made a bumpy road for Australian Motoring Enthusiast senator Ricky Muir.

The Australian Motoring Enthusiast Party (AMEP) has taken only a month to hit its first serious bump in the road.

Since taking his seat on July 1, Victorian Senator Ricky Muir has sacked his chief of staff and the party has been engulfed in rumours of undermining and backstabbing.

Senator Muir dismissed Glenn Druery – known as the “preference whisperer” for his role in getting micro-parties elected – on Thursday night.

Neither will say why.

“I acknowledge and appreciate the contribution Mr Druery has made to my team and the support he has given me personally,” Senator Muir told AAP in a statement.

Asked by AAP whether he had a statement about his departure, Mr Druery said: “I wish Ricky all the best.”

But he told Sky News that AMEP’s national officer, Keith Littler, who is on the senator’s staff, had been undermining Senator Muir.

Mr Druery said there was a “plan Z” to make Senator Muir resign and to install Mr Littler in the seat.

Liberal Democrats senator David Leyonhjelm said Senator Muir, who provides a crucial Senate vote for government legislation, was probably better off without Mr Druery’s help.

“Glenn Druery is great at numbers, he is excellent at counting the preferences, but he’s not a policy adviser,” Senator Leyonhjelm told Sky News.

He got to know the adviser when Mr Druery was a Liberal Democrats candidate in 2010.

The drama comes after AMEP’s Victorian branch voted to revoke Senator Muir’s party membership and no longer recognise him as representing the party in the state.

The key crossbencher has faced criticism from fellow party members since he struck an agreement to vote with the Palmer United Party, and has been under pressure to stand aside.

Senator Muir described it as “a bit of an internal party issue”.

“The aim of the game for me was, no matter what, don’t let anything distract me, just take that seat and represent the constituents,” he told the ABC.

Mr Littler has said the Melbourne meeting and vote on Wednesday was unauthorised and its decisions did not stand.