Vacuum Modulator on 95 Corolla

My buddy has a 95 Corolla - i think with 1.8 eng., he is convinced for some reason (i think it throws some kind of SES code - not sure which one) that he needs new Vacuum Modulator valve that connects to the EGR, but he is also convinced that color of the valve's cap matters as well. I found for him a used valve with purplish (could be faded red) cap, he thinks he needs the blue one (currently on the car). Is there any validity to his convictions? And I mean only VM valve related :grinyes: