Hey everyone been a lurker ever since I picked up my baby and have been trying to learn as much as I can about fixing it myself because I am a broke 20 year old college student! yay me. Anyways the issue I am having it that when driving and released from being on load (in gear), it will drop to a low idle and bounce, stumble and almost want to die around 250-500 rpm than after about 5 seconds it will return or find its normal idle at 850 rpm and run fine. While it is doing this for about 5 seconds during that time period I can blip the throttle once or a couple of times and it will return to its normal idle without having to wait the rest of the 5 seconds. When I start the engine when it is cold it idles fine and drives fine until it reaches operating temp. Also occasionally not all the time when I start the car when warm it does this as well where it will idle and bounce around 250-500 rpm. Anyones input is really appreciated, I've been scouring the forums and have read some threads, I just cleaned my throttle body and the air valve and tried my best at checking the tps with a multimeter and feeler gauges (it looked fine) as well as checked for vacuum leaks. and the problem still exists. So if any one could point me in the right direction or tell some things to check that would be great thanks!
oh and its a 1992 pickup 3vze v6 4x4

 

I am living in my Toyota pickup! When Coronavirus hit, I opted to move to a rented room in the country as unemployment could not sustain me in an apartment. The night before moving my 86 pickup gave up-electralisis ate the head wall through.
All the years that I drove the truck people were asking me if I would sale it and complements about it everywhere I went, so I guess that all convinced me to buy another engine and charish the vintage charm.
It’s been about six months now and I’ve been through three mechanics and $1500.00 in unsuccessful attempts to make this truck idle.
The big issue now is a broken BSVS valve that is no longer manufactured and if you do locate one on the www it’s in China or is immensely marked up in the USA.
I have found Toyota’s 22R engine to be the biggest pita and not to mention that it has no power or speed. This is the most expensive automobile repair I have ever experienced and the worst part is that I’m so invested that I can’t change my mind and jump ship. I’m sleeping in the bed with a camper shell tonight because I’m outta gas and this bank closed at 3pm. I have a check for $200 one of the shops refunded me and I will be going to TOYOTA dealership to pay $110.00 for a plastic BSVS valve.
This BSVS valve is a little plastic part that looks like a temperature sensor and it sticks up about 2” on top the intake. You try working around the carburetor and accidentally bump it and it is broke! This part is responsible for so many things regarding the carburetor, choke, and basically it is the sole heartbeat of the truck and it is plastic!!!!
I’m trying to say that I have become homeless by Toyota and throughout this adventure I have come across a few design flaws; the heater hoses come through the firewall directly above the valve cover so that you cannot remove the valve cover without some real struggle! I find this so irritating since this engine has so much chatter in the head and valve adjustments are so in demand. But the plastic BSVS valve is the one that takes the cake! I’m going to get mine encased in something to protect it and advise anyone else to do the same.

Without a three ported BSVS valve, the Toyota pickup will not run! It’s the other key that you never knew you had.

 

The 3vze, 22r carb, and the 22re/22rte are different animals, also different year models may have their own quirks, specific to that year model.
normally at the END of a post, below it (related topics) Are several RELATED threads that lead to MORE RELATED threads, so on and so forth... some have no conclusion or resolution and some do, you just have to keep wading thru the information till you find one that works for you.
Then please report what didn't work and what did work so others can gleen from your experience.
I'm only semi fluent in 22rte and completely unfamiliar with the 3vze or the 22r. Good luck and keep searching.

 

So tried to adjust my tps today and I think I did it right I listened to the lc engineering pdf. Still does the same thing. The dash pot is stuck being closed when vacuum is being applied and the throttle linkage doesn’t touch it. Also the throttle linkage sticks and I can push it back the rest of the way with my hands and it will return to normal idle. Is it possible for the dashpot to break? Any thoughts? And what is the sensor that tells the ecm my coolant temp? The coolant temp sensor? Could that have something to do with it?

 

It was the aftermarket cruise control that was causing the issue

 

Good find... thank you for posting your conclusion, it will help others in the future