240 General: total brake failure

[Marlen]

Last week I experienced total brake failure ... brake pedal flat to the floor ... on my 1989 240 wagon. Fortunately I brought it to a stop after numerous scary blocks. Got it towed to a mechanic and waited until they looked at it today. Unfortunately they told me that they could not reproduce the brake failure, the brake fluid was adequate. They told me the pedal was totally firm. They had assured me earlier that once they had it on the lift they would know exactly what was wrong. I'm panicking because I truly don't ever want to have that experience again. They offered to keep it for another day and check again. I'm not at all mechanical. I'm hoping someone can tell me (and the mechanics) what might have gone wrong.