Hi guys

When starting off from cold my brake pedal travels excessively to the point of scaring the **** out of me! Nearly took out the security gate of my SES depot this arvo Once I have driven it for a few minutes, the pedal returns and the brakes are fine again. Now, I assume that it has something to do with the servo booster? My question is "what"? and the inevitable "how do I fix it? BTW 84 RRC. 3.5 V8

Jez