On my 1995 tacoma 4cyl 5spd the rpms drop when i hit the brake. I disconnected the brake booster and it did still did the same thing. Does anybody know what this could be?

 

that is normal for the rpm to drop when brake is depressed. i believe there is more then 1 line that goes to the booster so if you disconnected and plugged all of them the rpm shouldnt fluctuate with the brake. if you just pull the hose off the idle will drop because of the massive vaccum leak created

 

i unplugged the main hose to the booster and put a big bolt in it and taped it to create a seal and the rpm still drops. It idles at around 1200, and drops to about 700

 

so lets say your coming to the stop light you stop and hold your foot on the brake while sitting the idle drops to xxx does it recover back up to normal with brake still applied or does it continue to idle low until you let off.

 

I believe your idle is too high. When your idle is over 1000 rpm and you press your brake the ECU tells your engine to drop idle. Lower your idle to below 1000 rpm (maybe 800) and try pressing your brakes and see if it still does it

 

no it stays at that rpm then when i let off the brake it goes back up too the regular rpm.

 

ill try that and see what happens

 

What were your results?