What does a particular VSV do? See excellent attached diagram.

[Ian R.]

Welp, I went back at it, and after perusing an AC thread, I decided to undo the grounding of my coolant temp switch, and voila! My idle-up diaphragm only kicks in when I’ve got my AC on . Seems like grounding the CTS caused the idle-up diaphragm to always be active.

This is exactly the answer I need for an issue I have been struggling with.

I had a failed air idleup diaphragm. It was basically routing unmetered air through the large port, through the diaphragm activation port, through the vsv, then back through the manifold side port of the diaphragm (if that makes sense). This cause the engine to idle about 200 rpm higher. When I installed a new idle up diaphragm it did not seem to fix the idle issue. Then I notice that when I turned the spring retain screw on the idle up diaphragm it change the idle. It did not make any sense at first. Why was the VSV activated when there was no load from the PS or A/C? THE COOLENT TEMP SENSOR WAS GROUNDED TO THE ENGINE BLOCK! I would have never figured that out on my own. I removed the coolent temp switch wire from ground and the problem resolved. Thanks for this!

[Knibbzy]

Hey Guys so I did an Oppsie, I was trying to tune up my Toyota Spacia YR22 4YEC van





Sorry for the big photos

Anyway I grounded the terminals and I have gone to unplug what I thought was the VSV ISC but I believe I have gone to unplug the AC VSV this one



And I have gone to push the release tab for the connector and being old and brittle and alot of heat gets generated in this small space i guess old cars I have gone to push in the locking tab to pull the connector and it has snapped on me I want to replace the connector and was wondering if anyone knows where to get just the connector I have found this one it looks like it might be okay but if anyone knows definitely where I can get the connector it would be much appreciated.



I was also looking at some stuff and have found what looks like dodgy repair work or mechanic not being honest with previous owner as I have recently picked up the car. I am gonna have to fix a few things




As you can see for the EGR System the BVSV Switch is broken and the vacuum lines for it has been blocked of into itself so I will be getting a new BVSV Switch and putting the vacuum lines back into that.

Another Question I have is the spade terminal that is plugged into the sensor is that the coolant temperature sensor for the dash cluster coolant temp, my cluster coolant gauge is currently broken and need to get it fixed I am just hoping that this is only a coolant gauge temp sensor. I believe the brown plug sensor is the cold start injector sensor and the green plug sensor is the coolant efi sensor for the fuel mixture. I can get away with not having my coolant gauge on the cluster not working as it is winter and car most likely wont overheat to much i just keep an eye on my coolant overflow bottle and make sure its topped up to full every so often, another problem i have is the overflow sensor is faulty to even if overflow is at full the sensor reads that the coolant is low I have it disconnected for the time being until I try and source that unicorn sensor part.

And finally the last thing the car has been idling at 1500rpm and I wanted to adjust it back to the recommended 700rpm with VSV ISC disconnected, this is where i stuffed up and disconnected the AC VSV and not the ISC VSV I am gonna double check my idle adjustment again, but what I need to do is basically check timing is 12 btdc so you have to adjust your idle to 700rpm M/T and turn dizzy until you reach 12 degrees btdc max allowed rpm is 850 once that is all good you can move to adjusting idle speed this is where you disconnect the VSV ISC and adjust idle screw to 700rpm plus or minus 50 and done your tune up should be all complete.

My problem is after I lowered the Rpms down to this mind you I did it with the wrong VSV connected so I will double check again, anyway after adjusting the idle speed down to around 700rpm I had the car off and it cooled down, when I went to crank the car it would crank over idle for a little and then die where as before it would just idle straight away but mind you it was idling at 1500rpm and the idle screw was turned all the way out, but on the second crank I held my foot on the accelerator at 2000rpms to get the car warmed up and after 30 seconds the car started idling fine on its own and was driving good. So I am wondering if something else is wrong but I am gonna fix all the things I have mentioned and then I will give and update on the outcome.