Hispania team principal Colin Kolles has renewed his threat to protest exhaust-blown-diffusers if they're used at next weekends Monte Carlo Grand Prix.
He has gone as far as to write to the FIA, threatening a protest if they are not banned immediately.
Currently, all the teams on the grid but Hispania, Virgin and to an extent Williams, are using the EBD system which blows hot exhaust gasses over the rear-diffuser, even when the driver isn't on the throttle.
This increases a cars downforce significantly, but increases the engines fuel consumption as the car has to use more fuel to create the same level of gas when the car is coasting, compared to when the throttle is fully depressed.
Kolles says this device is against the regulations and, if the teams continue to use them in Monaco, they will launch a protest with the FIA stewards, possibly resulting in disqualification of any car found to be running with the device, that, despite the FIA giving the teams a grace period until after the British GP to drop them.
"The only reason why we are not considering [a protest in Spain] is because we were not involved in any sporting decision today," he told the BBC after the race.
"It's clear that the other cars are illegal," he claimed.
"We agree absolutely with Charlie Whiting's view and, by the way, we are not the only ones who agree. I think that if this is not going to be stopped before Monaco then we have no other choice [than] to make a protest.
"You cannot influence the aerodynamics with hot exhaust gasses, you cannot influence the aerodynamics by any movement like gas pedals or moving devices on the engine, or whatever. So this is illegal and it brings the other teams a huge advantage," he explained.