88thunder

Howdy,
I've got the intake off to do some work on my 88 4runner. V6 SR5, The little tits on the valve are broken off. I am just wondering if it"s something I really need. I live in CT so emmissions aren't a huge deal. There are no hoses that go to it. I'm the 3rd owner and not sure if they were ever there. Looking for help from the experts. Thanks.

xxxtreme22r

pics might help as there is alot of stuff with vacuum lines and stuff on that intake manifold.

88thunder

K. I'll try to get some uploaded tonight. There's nothing for it to hook up too. I'm perplexed!

MudHippy

Well it is something I do know alot about. Not that there's much to know. It's a pretty simple system. Basically, NO, your engine doesn't require it. It's part of the EVAP(evaporative emissions control)system and is only there to make use of gasoline vapors from the fuel tank that may otherwise escape into the atmosphere as HC(hydrocarbon)emissions. If you don't want to fix it you should atleast make sure that the EVAP purge port(marked P)on the throttle body is plugged/blocked off thoroughly. Or you're going to have a substantial vacuum leak. Someone must have already done so. But in case they didn't....

Here's several threads I've participated in regarding the EVAP and other emissions control systems. With all the hows/wheres/whys on dealing with the numerous components of such. Including plenty of info regarding deleting said systems.
https://www.yotatech.com/forums/f116...emoval-202562/
https://www.yotatech.com/forums/f116...em-off-220660/
https://www.yotatech.com/forums/f116...-valve-129471/

Just know this, it's a beneficial system not only for the environment. And has no deleterious effects on engine performance when functioning correctly, likely to the contrary. Meaning it may save you some gas money in the long run by slightly improving the overall mpg achievable if restored to proper working order.

Sidenote: The BVSV(bimetallic vacuum switching valve) is also known as the TVV(thermal vacuum valve).

scope103

There are some who have been successful fixing the Thermal Vacuum Valve -- https://www.yotatech.com/forums/f116...ix-pics-84460/ I tried it, but on mine the plastic head had become "crumbly" with age and the fix didn't take. I bought a replacement at my local dealer in 2007 for $65.


And I agree with MudHippy's sentiments.

88thunder

Thanks for the help! I intend to fix it back to its working order. Thanks for the extra info. I am going to replace all of the sensors/switches back there while I have it apart. I got a code for a temp switch not working. Any advice would be greatly appreciated.