Honda engine failures raise concerns

Losing four engines in a month would be a troubling trend for any manufacturer. Blowing four motors in six days, as Honda has experienced at Indianapolis, could bring the worrying to an all-new level.

The Japanese brand suffered two engine failures on Saturday during the Verizon IndyCar Series' IndyCar Grand Prix road course race at Indy, and added a pair of broken motors during practice for the Indy 500 – one with Graham Rahal's car on Monday, and another with Sebastien Bourdais' car Thursday afternoon. The recent problems follow an explosive April where the manufacturer lost numerous engines, and with a win to defend at the 500, reliability has become an unexpected question mark.

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Asked if the Indy practice failures were related, Honda Performance Development race team leader Allen Miller told RACER: "They're under investigation and we'll do our best to address any issues before the race."

Although HPD would not be drawn on the source of the problem, chatter among Honda-powered teams has pointed to one specific internal component failing; those failures are said to have come while running in a particular RPM range.

Honda's engines have been impressive for their power in 2017, but the spate of breakages have led to speculation the motors have been wound to their limit.

"Obviously, to lose an engine is frustrating but I know the Honda guys are pushing these things as hard as they can," Rahal said on Monday.

For Bourdais, who also suffered one of the failures on Saturday, blowing two engines in such a short span – and while trying to turn as many laps as possible before rain is expected to fall Friday through Sunday – has been especially cruel.

"Same issue as Saturday: The engine let go," Bourdais said. "I don't know. You're going to have to go ask that question to our guys at Honda. Clearly there's an issue; I don't know what it is. I'm not quite sure they know what it is. That engine was almost new."

The Frenchman has placed his faith in Honda to find a remedy before the 101st Indy 500 on May 28.

"There's clearly a big issue and we need to find a way to fix it because otherwise it ain't gonna be pretty," he said. "You can't race without an engine. We have a powerful and competitive package, but you have to see the checkered flag."