"We were battling for the lead and it was going back and forth between about three different people," said Cox. "Stage seven we got the lead back, but at the same stage I was realising the car wasn't right. On the corners we were losing power and the car kept cutting out a little, but we got to the end of the stage."
Stage eight was cancelled.
"On nine . . . the car started smoking. I thought it was something with the motor, but we carried on and hoped to get to the service that night.
"We started stage 10, but unfortunately that stage was super wet and super muddy and struck a corner that was really muddy. I turned in and just went straight and went off the road and hit a little bank. That was it for the day."
The crew's "big night on the car" revealed the turbo problem and, with little damage from the off, Cox was able to resume on Sunday.
"They got the car back up to racing standard and we got back out onto Sunday's stages.
We set some top stage times again, won a stage and were right back at the front again and had a really good day of racing.
"It showed why I love the event, but I still can't conquer it. There's something about Whangarei that loves us and hates us at the same time."
After two rounds of the championship, Cox now sits in a lowly 13th place overall.
"The next three [rounds] are single day events so we need to look to get some good points to recover where we are. It's still not bad just yet, but we have to get some good points in the next couple of rounds to get back into it."
The next round is the Canterbury Rally on June 4.
"[Before then] we have to make sure nothing else has been damaged, but luckily when we slid off I don't think it did too much damage as it was soft."
The rally was won by Rangiora's Matt Summerfield.