mtrdrms

Hello collective wisdom. I'm doing head gaskets on a 93 3.0 and I broke the plastic vacuum fittings off the bvsv that screws into the water bypass area. Can I bypass this thing? How necessary is it to engine operation? New ones are around $40 and if I don't NEED it....
Thanks.
Andy

scope103

If you just bypass it (connecting the evap canister directly to the vacuum port on the throttle body), you may have driveability issues when cold. Or not. If you do that, please let us know what you find. (Particularly in cold weather.)

If you don't connect the evap to vacuum at all, the evap could fill with enough gasoline to condense it and have it drip out the bottom. Not good.

nordicwargod

On my 22r the bvsv is very important, if you still have your egr valve! The bvsv is a temperature activated vacuum switch. When the engine is warm it opens and allows vacuum to the egr modulator. Without it the egr won't open at all. And contrary to some opinions on this forum the toyota engines with this valve were designed and engineered to operate with one. Remove it and you will have higher combustion temps and probably pinging.
Pick one up at a junk yard or on ebay. If it fits it will work, its only a switch so one off a 22r or other toyota will probably be fine.

scope103

The bvsv (bi-metallic vacuum switching valve, more commonly known as the TVV, Thermal Vacuum valve) on the 3VZE connects the EVAP to throttle body vacuum. It has nothing to do with the EGR.

The 22r uses a different system, and it DOES have a bvsv in the EGR circuit.

And nordicwargod is right; removing/bypassing parts of the EGR system will almost always lead to a bad result.