Fox T-Bird/Cougar Forums

Technical => Engine Tech => Topic started by: SRBird on July 27, 2007, 01:07:39 AM

Title: Vane air meter
Post by: SRBird on July 27, 2007, 01:07:39 AM
I'd like to use a vane air meter like those used on the Turbo Coupe as an air flow meter for a project. The problem I encountered was that I can't find a diagram indicating which connector is for what. The meter I have is from an 89 Probe. It has 7 connectors, from left side I gather the first two are just a switch indicating whether the vane is open. The third connects to the board and also the temp sensor. The next two connect to the board. Sixth goes to the sprung sweep arm that is rotated by the vane and sweeps an arc on the board. Seventh connects to the temp sensor. My problem is that I haven't been able to feed a 5v signal on one connector and get a return signal variable with the opening and closing of the vane. Seem to only get full 5v back.

Anyone have any info or experience with these? I'm a little stumped. What I thought could be straight forwards, isn't! DOH
Title: Vane air meter
Post by: softtouch on July 27, 2007, 06:41:21 PM
The 84 EVTM shows the vane air flow meter as just a variable resister ( potentiometer) that is mechanicaly operated by the air vane.
With your ohm meter find the three connectors to the resister. Each end of the resister and the movable arm that slids along the length of the resister.
For this to work, current must be flowing through the resister. 5 volts on one end and ground on the other. Then the movable arm will pick off a variable amount of the voltage as it slids back and forth.

If you just put 5 volts on one end of the resister, you will have 5 volts on the other end of the resister and on the movable arm.
Title: Vane air meter
Post by: SRBird on July 29, 2007, 02:01:24 AM
Thanks a bunch. I'm getting variable feedback of 0.97 to 4.9. Now to calibrate it for v to cfm values.