Renault hopes that Formula 1's governing body continues to push to ensure rival manufacturers are not using oil to boost their engines.
The French outfit successfully lobbied for tighter rules to enforce the thorny topic.
"Much has been done in relation to these loopholes, but we continue to collaborate with the FIA to ensure they have the tools to monitor them properly," Cyril Abiteboul is quoted as saying by Ekstra Bladet newspaper.
"So it's not just about good rules but also how to monitor them.
"I'm sure the rules are clear, but I'm not sure yet about the FIA's capacity to monitor them."
However, Renault itself is said to have been the subject of a separate complaint over the winter, apparently from a customer team which suspected it was not being treated fairly regarding engine supply.
"It's a concern for customer teams and for good reason. They should be treated equally and we've always done that in our 40 years as an engine supplier," Abiteboul insisted.
"But we must also accept that there will always be small differences. For example Red Bull has another partner so they use different fuel and oil.
"But we didn't force them to and so they could have used our partner."
The 2018 F1 season begins later this month with the Australian Grand Prix.