Adjusting Fuel Mixture (Problem with checking idle duty cycle)

[JamesDean]

Hey everyone,

I have, for a few days anyway, an Aglient oscilloscope, so i thought I would look at my fuel mixture on my m103. Turns out it was not right.

I'll post up the measurements later, I was pretty close to getting it to spec when I lost any reading @ idle after 30 second from start...

My scope shows nothing but noise..

When you rev the engine to ~1000rpm, I hear a vacuum valve pop open/closed (seems to be connected to a pot of some sort behind the headlamp and the intake manifold) and the waveform comes back to life.

I checked the o2 sensor and its fine. fluctuating voltages.

Anyone have any clue as to why i would get no duty cycle reading from the x11 (pin2 +,pin3 -) port @ idle?

Thanks,

Kris