About 2 weeks ago my engine cuts off because one of the wire to this vacuum switch (part#89570-12290) near top left ripped off. I was able to fix it enough to get it home. I then solder the wire and was able to drive the car a few more weeks with it. But a few days ago the car had the same problem. I believe the connect where the wire was solder together was not strong enough to make a solid connection. Its there a way to bypass it to keep my car running normally?

The one with the green plug? Thats the electric idle up plug. Turns up the idle to compensate for electrical drain, like headlights and stuff. Just unplug it, cap the vacuum lines and trash it.
You do not need it to run. Might notice 100rpm drop at idle with the lights, heater, stereo, and blinker on. lol

i13ethat wrote:... my engine cuts off because one of the wire to this vacuum switch... ripped off.

If your engine cuts out because that valve is not working, your idle speed must
be a bit lower than stock (850-900 rpm). As said, try raising the idle speed by
turning the screw down the tube on the side of the throttle body. You can just see
the open end of the tube at the bottom of your pic. Turn the screw out (ACW) to
raise the idle.

Fixing the wires should not be a big deal... that plug will be common on old Toyotas,
and you can most likely pick one up from the junkyard.

Cheers... jondee86

the job of this valve is to raise the idle about 200 rpms when a) you press the brake pedal b) when you turn on the lights c) when you turn on the blower d) when radiator fan opens. Sorry if i forgot something!

I replaced the valve and the engine is now running.

the later models or the 4afe had an extra vacuum valve for the power steering wheel.When you turn the power steering the valve opens and idle rises.