I adjusted the spring tension on my 85 GL Digijet 4 days ago.  The effect between spring tension and 02 sensor output went backwards from what I expected.

I started with 1.37 AFM volts at idle. I turned the notched black wheel in the AFM 10 notches clockwise, the AFM volts went to 1.10. Which I expected. 

But the 02 started at .75 volts open loop, and after the spring tension adjustment the 02 went to .9 volts. Opposite of what I expected.

So I moved the AFM tension to 10 notches less than I had to begin with, the AFM volts went to 1.48. Which I expected.

But now the 02 went to .7 volts, the opposite of what it was supposed to do again.

The throttle valve controls the air to the engine and I didn't change that, all I changed was the open loop AFM signal to the ECU. With the greater AFM volts it should have added more fuel  not less.

I left it at the 10 notches less and the .7 volts  02, and put it back in closed loop. The idle surge is gone for now (usually happens on a warmer day anyhow) and the digitool is hooked up.

No I'm not crazy, or at least not since I got out of my 20's.

Mark Ingalls

[text/html]