Boy racers have until next July to get rid of modified exhaust pipes on their cars, under an EU directive on noise pollution.
The law which comes into effect next year will ban the exhausts as part of a range of measures aimed at reducing noise emissions.
But it's not yet clear how the government will enforce the rule, or whether drivers could face fines for having enlarged exhaust pipes.
Fine Gael MEP Jim Higgins says it should be made part of the NCT test.