MBIE was also investigating, but the ministry itself had not confirmed the fuel was contaminated, its trading standards national manager Stephen O’Brien said.
“This matter is currently still under investigation and the existence or source of any potential contamination has not been confirmed at this stage,” he said.
The Bluebridge Connemara lost power and drifted for more than two hours in the Cook Strait in September.
“This investigation will also include determining whether any potential contamination occurred on the vessel or in the supply chain.”
Resources Minister Shane Jones said he was not concerned about any widespread problems with fuel in New Zealand.
His office told RNZ he would await the outcome of MBIE’s investigation.
Meanwhile, the union representing ship masters and officers said StraitNZ and Maritime NZ should have fronted up on the Connemara’s problem immediately, in case it happened to any other vessel.
Maritime operators needed to know how to prevent further issues, Merchant Service Guild’s vice-president Iain MacLeod said.
But Maritime NZ said testing showed there were no problems with fuel supplied out of Wellington, and if there were, it would have notified the appropriate people.
Transport Minister Simeon Brown said he was satisfied with Maritime NZ’s communication with him and the public.
