E4ME Theory of Operation

[Shark Racer]

Hi gang,

Long time no chat. I'm venturing into a new horizon with QJ tinkering. Playing with an E4ME - not just a general rebuild and tossing it onto a car, a little more than that.

Anyways, I was wondering if anyone knew how the feedback system worked? It seems from my reading (1980 Corvette service manual) that it relies on TPS, RPM and lambda sensor only.

From what I've read, it basically cycles the solenoid to full lean when the O2 detects rich and full rich when the O2 detects lean. Below a certain TPS setting it does the same, but inverted as it's more concerned with idle air than jet orifice restriction size (the solenoid controlling both the amount of idle air available and the position of the metering rod in the fuel orifice).

RPM's only impact (as near as I can tell) is to prevent operation during cranking and leave the solenoid at full rich.

Am I off? Any recommended reading for trying to understand this system better? (Wiring diagrams, preferably with information about signal voltages, PWM, etc)

Thanks in advance!

[novadude]

It would be really cool if someone would make a control box to run one of these on a performance type application.  It will likely never happen, but it seems like the best of both worlds - carb simplicity with precise cruise a/f control.  Plus, E4ME carbs can be had cheap.  I'm sure one could build the electronics and sell a "black box" for a few hundred dollars and make good margin.  Wire up the box, install an O2 sensor, and you are ready to go.

Like I said - it will never happen, as 95% of the "hot rod" community doesn't appreciate or understand the Q-jet.