Help with a Renault 5

I have a 1991 Renault 5. It starts and runs great. However, when you step on the brake, the engine turns off. What could be the problem? Within the past two months I have replaced the starter, heater core, alternater, and the headlight/turn signal/horn switch. Has anyone else had simular problems. Thanks,

Jeff

when you are sitting still and you press the brake pedal does it cut out then also?

could be a dirty rpm sensor.
Is it also when you disengage the clutch and brake?

Derby