i'm an OBDI @ '94. but no code 71..
'94 FJ80 - Why no Vacuum to EGR?? (1 Viewer)
- Thread starter LandCrawler
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I have 2 new check valves in hand to put on ,
I'm still unclear as to vacuum operation of the port on the other end of the system.... on the bottom of the intake ... seems like that would have vacuum .. it tees a couple times and goes to the vsvs under there... which seems like it would cancel out the vacuum sucking the other side of the egr ( from the throttle body ports) ... i have no vacuum at the vsv on the intake port side ... but there is vacuum on the throttle body side of the system.
not sure of that is any clearer than thick mud ...
I'm still unclear as to vacuum operation of the port on the other end of the system.... on the bottom of the intake ... seems like that would have vacuum .. it tees a couple times and goes to the vsvs under there... which seems like it would cancel out the vacuum sucking the other side of the egr ( from the throttle body ports) ... i have no vacuum at the vsv on the intake port side ... but there is vacuum on the throttle body side of the system.
not sure of that is any clearer than thick mud ...
ToyotaDon
I am here
I've always understood that the VSV side is just supposed to vent the vacuum, or block it to allow the EGR valve to be opened by vacuum from the modulator. The check valves are related to other systems, so I don't see how they will have an effect. If you still want to test them, you can do it by blowing (with the mouth) through them. One way will flow, and the other will be blocked.
Bottom line, it sounds like your VSV is not working. It's common for the VSV to fail, but you should first check for power and ground according to FSM instructions. If you have to replace it, look at the relocation options.
Bottom line, it sounds like your VSV is not working. It's common for the VSV to fail, but you should first check for power and ground according to FSM instructions. If you have to replace it, look at the relocation options.
I'll check it again ;->
Follow up, failing emissions still this year. had a shop do 5 gas test on it, they told me it was the cats. been there, done that, didn't make me pass. In fact had the same #'s. It ended up passing from blocking the EGR line. Dug through everything under there, tvv, vcv, vcv egr wtf.
SO, just registered in a non emissions county where i "store" it. problem solved. Options wide open now.
