idle problem fuel pressure up vsv 7mgte
 

Ok I have a 1987 supra 7mgte with a r154. My idle drops when I brake or hold the window switch down and idle will drop down to 500rpm when left sitting. And my fuel pressure up vsv has a broken wire. When should the vacuum from the vsv stop. Would a bad brake master cylinder cause the idle to drop? Any help would be greatly appreciated.

I know someone has some insight. Or atleast help me eliminate some things.

Sounds more like a charging system problem. Might just need to install new brushes in the alternator. Check and see if the RPM drop occurs when you operate other circuits (ie. headlights, hazards, heater). The fuel pressure VSV is VERY important and should be fixed as soon as possible but it's not the source of these symptoms.

New upgraded alternator. My brake go soft and I've bled them several times to where there is all new fluid. Could my master cylinder or a bad brake booster cause any of this? Those are suggestions from people. Oh and it does it no matter what's running radio, headlights, fog lights, ext.