"Those three first races really hurt our title bid," said Hartley after arriving in Japan. "By not finishing, you get no points and Le Mans really hurt us.
"We had been really fast and strong in the races we didn't finish. At Silverstone, I crashed when leading, at Spa, we were leading when we got a puncture that caused a gearbox issue and, at Le Mans, we led the race early on before the water pump failure.
"We were leading all three races before something happened, so we have been really strong all year. There are a lot of variables in motorsport and that's racing, I suppose, especially in endurance racing."
Hartley can't put his finger on what suddenly took them from zero to hero and isn't dwelling on the issue. He, Webber and Bernhard have just been focusing on each round and going about the business of trying to win races. Although there is a mathematical chance they can defend the WEC title, making up 52 points from a possible 75 is a big ask.
However, second place is a mere 14 points up the road and Hartley is sure, if their charmed run continues, they might just be able to topple the Audi of Loic Duval, Lucas Di Grassi and Oliver Jarvis.
"We arrived in Japan with good momentum after three wins on the trot for car No1. Fuji is a track I enjoy and it's a track that has produced great racing over the last years in the WEC. I expect another tough fight, and our goal and focus is to continue our winning streak," he said.
"Mathematically, we're in the title fight but we're just going to concentrate on winning some more races. The points will be what they'll be, and second is definitely on. The last three wins have by no means been easy and everyone else is looking pretty fast.
"We're up for the fight," said Hartley.
Being a prototype class there is constant evolution for all the cars in the LMP1 category. Things change from race weekend to race weekend in the never-ending struggle to get the best out of the car, its aero package, its performance, its hybrid technology and, of course, more pace. This weekend is no different and Porsche are hoping a number of small improvements will be the key to another win.
"The last part of season is not going to be easy especially with Audi showing really strong pace. We've haven't done anything fundamental to car over the past rounds. You're allowed three big aero changes, which we have had, and our last big change was a couple of races ago.
"From now on any other updates will be small set up and system changes that won't drastically change the car. It's a constant development and evolution with these cars," said Hartley.
The seventh round of the 2016 season is held at the Toyota-owned Fuji Speedway, located just a few kilometres from the Higashi-Fuji Technical Centre, where the manufacturer's LMP1 car is built.
The track is renowned for its 1.5km-long straight, the second longest on the calendar after the Mulsanne Straight at Le Mans.
The rest of the circuit is tight and technical and a challenge to drivers and engineers to get the right combination of downforce and speed.
