1990 Trofeo .. brakes pedal goes hard .. loss of
There are two things to look for regarding this problem. You have the "teves" ABS system, as do I in my 1989 trofeo. They were NOT that good, and tend to be somewhat trouble--prone. I DID have the same problem you do, mine was the ABS pump relay. There are two brake system relays mounted on the firewall of our cars, near the center, above the A/C blower motor. One is for the pump--the other one is for the whole brake system. If the pump relay goes bad(due to it running too much, from a "bad acumulator" which I DID have--and you probably do too..), it will not turn on the brake pump, and if the acumulator is either bad, or discharged...you will NOT get ANY power assist at ALL!! Our cars do NOT use vacuum brake assist--it is ALL done by the hydraulic pressure, stored in the accumulator. The relays are only about 10 each, and not hard to get. Another somewhat possible problem is the brake pressure switch, which triggers the pump relay, and it sometimes goes bad. If so, it causes the same problem as the relay. It is on the brake master cylinder assembly, and has about 4 wires or so on it
Also...you may have a bad accumulator. This is the ball--shaped thing on top of the master cylinder.It stores brake pressure, between pump runs. If it goes bad but the pump still works...you WILL have brakes, but SOMETIMES...the pedal will be hard at first, and then work. They go bad after some years of use, and mine was bad. A new one is available from GM, for about 150.
Once these "sore spots" are taken care of...the Teves system DOES work nice, and stop quick. Just have someone check these things that knows what they are doing. Good luck with your Trofeo--I love mine.
on Mar 16, 2019