1973.5 CIS Throttle Position Valve/Sensor/Regulator

[Jay Laifman]

Am I missing something? I am trying to see if my throttle position valve is working. I actually have a few of them. I have tried to blow in one of the ports, and turned the throttle position, but I never get air going through.

As I understand the throttle position valve, when the throttle is turned to either end (idle or WOT), it opens up the valve and lets gas through, thus reducing pressure, and richening the engine.

So I would think that I should be able to blow through when it is at idle or WOT. I thought failure mode was the valve always letting air through.

Is this wrong. Or does it just take more pressure than I can blow with my mouth?


The reason I ask is that I currently am not using the valve. I want to start using it again. So I want to make sure when I put one on, I put one on that is working. I recognize that if it was on the car, I could use the fuel pressure gauge to see if it drops/increases based on throttle position.