Zhou Guanyu says he has no idea what caused his poor start at the Hungarian Grand Prix on Sunday.
Lining up in a career-best fifth place, Zhou lost the revs in his Alfa Romeo car moments before the lights went out to signal the start of the race.
The Chinese driver was slow pulling away out of his grid box and was swallowed by the pack behind him on the run to the first corner.
“No idea [what happened], I need to have a look,” Zhou said. “I was holding the revs before the four lights and then I lost all of the response from the throttle.
“I was starting with basically zero throttle, I was flat on the pedals. We need to see. It’s really disappointing because I think we’ve been really good on lap one and starts.”
Zhou’s race took a further step in the wrong direction as he locked up into the first turn and tipped into the rear of Daniel Ricciardo.
The contact resulted in Ricciardo coming together with Alpine’s Esteban Ocon, who, like team-mate Pierre Gasly suffered terminal damage and retired from the race.
“I was trying to brake as late as I could, trying to get some positions back,” Zhou said.
“I got into the dirty air of the cars ahead, unfortunately, I locked up into them. Not where I wanted to be, but the race was pretty much over after the line for me.”
The stewards deemed that Zhou was at fault for the contact and issued him a five-second time penalty as well as two penalty points on his Super Licence.
“It’s very disappointing, but unfortunately there’s nothing more I can say,” he added.
“We need to see more in detail what happened there because it’s strange. It never happened before at all.
“I tried to recover before the five lights, tried to go full throttle but nothing was happening. My start was actually a pull away, it wasn’t a start. That’s why you saw my car wasn’t moving.
“We lost the chance today, we need to continue to have a strong car, especially on Saturday and make more chances happen in Sunday’s race. So not the best day for the team.”