I checked all my vacuum lines and still nothing. Moved the control arm up and i had heat until i let it back down then back to cool air again. So im positive that valve is no good. So can i bypass it for awhile and leave it like that? Any consequence to that?
Bypassing heater control valve
- Thread starter 917mgte
- Start date
A buddy of mine used a zip-tie to hold the valve up in the up position for a little till he got a hold of a new one. It didn't hurt anything and he had it on there for a couple weeks.
You can also just put the vacuum line strait to the port on top of the valve (bypassing the electrical vacuum valve) so anytime there is vacuum the valve is held open.
917mgte;1662317 said:
Ive been using zip ties for over a year now, no issues. Won't hurt anything. Doing this issue the ghetto way > no heat at all.
Zipties are not needed unless the valve is frozen and vacuum will not pull it up.
Apply straight vacuum to the valve(which involves swapping to hoses(so hard)) and when the engine is running the valve is open you have heat.
Zipties also work. Used them on my old car.
Apply straight vacuum to the valve(which involves swapping to hoses(so hard)) and when the engine is running the valve is open you have heat.
Zipties also work. Used them on my old car.
While it's true I've fixed a couple the typical failure mode is unrepairable. After going through two of my own I finally gave up on the stock ones and substituted an industrial miniature three-way that permanently solved the problem. It was also cheaper.
Been a while but this one should work:
http://cgi.ebay.com/Miniature-pneum...ic_Hydraulic_Valves_Parts&hash=item45ee39859b
Get it in 12 volts with the grommet connector to keep the size down. Add some brass or plastic 1/8 npt hose barbs of the proper size, splice wires/use connector, and you're good to go.
Course, any three-way will work but small is good. If you use a 90 fitting on the side of this one it'll even mount where the old one went without modifying anything.
http://cgi.ebay.com/Miniature-pneum...ic_Hydraulic_Valves_Parts&hash=item45ee39859b
Get it in 12 volts with the grommet connector to keep the size down. Add some brass or plastic 1/8 npt hose barbs of the proper size, splice wires/use connector, and you're good to go.
Course, any three-way will work but small is good. If you use a 90 fitting on the side of this one it'll even mount where the old one went without modifying anything.
If you change your vacuum around and the valve lifts up on it's own then the solenoid is the issue which is about 90% or more always the issue. The solenoid is that little gold metal band that's loops around into kind of a box and is located on the left hand side of the valve. It has the electrical pig tail coming off it. If you take the valve off you will see that the solenoid comes off the valve every easy. Take it to your local U-Pull it yard and look for one like it under just about any 80's or 90's Toyota. It's just a vacuum switch and its used for all kind of purposes so don't just look at the heater valve location. I found mine mounted to a fender well in a Celica. I had to cut off the connector on the one I found and attach it to the connector on the one from my car but it fits and work perfectly.
Last edited:
No. Didn't take a pic and no longer own the car but it's not rocket science. Mounts upside down where the original one went using the same screw hole. Either remote the filter on a short length of hose or just stuff a bit of cotton down the port. Leaving it open won't hurt either but it's good to keep out dust.