Johnson had been leading the Michigan event with just five laps remaining when an engine failure – his second of the weekend – robbed him of victory.
Team-mate Jeff Gordon and Hendrick customer Tony Stewart also endured engine problems during the race, denting the former’s chances of making the Chase, which kicks off in just four races time.
Valve springs were believed to be the cause of all four issues, with Johnson confident that his team’s work during the week will ensure that there are no repeat failures at this Saturday’s IRWIN Tools Night Race.
“There’s a lot that goes into it (analysing engine failures) and I’m always impressed with our engine shop and how scientific they are about the analysis that takes place after a failure,” Johnson told Speedcafe.com and other media at Bristol.
“It looks like a bunch of broken bits and pieces to me, but they’re able to do oil composition tests… they almost trace it back ‘CSI style’ to see where it started. It’s impressive to me each time to watch the process.
“We certainly had some issues at Michigan, but they’re working hard on it and we won’t go to tracks with something that’s untested. We have multiple dynos in our engine shop, as well as Spintron machines , a lot of different ways that we can do duty cycles on the engines and test things.
“It’s safe to say that we were caught off guard in Michigan and the failures were unexpected, but the guys are on top of it to make sure that it doesn’t happen again.”
The events of last weekend brought an uncharacteristic post-race reaction from Johnson, who elected to flee the circuit without facing the media.
“There were so many levels of frustration that came through from missing the chase bonus points for a win, losing our championship lead… There wasn’t much else to say to anybody watching,” said Johnson of the .
“Clearly we had an engine failure so it didn’t make any sense to me to talk to anyone and point any more attention to our engine shop.”
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