The ECU has 3 inputs for idle.(reference Chilton)
1) Coolent switch
2) Micro switch on intake accelerator arm.
3) Wire from coil.
---RIGHT?---
So if the car idles smoothly when cold... but starts to act up as it warms
up... would it be a reasonable conclusion that the air bypass valve/solenoid
is working properly but the idle micro switch on the accelerator is either bad
or not adjusted right?
Here is my reasoning. The car starts right up. Idles great when cold.. hence the coolent temp sensor switch is doing it's job of telling the ECU to diddle with the bypass valve.
The car warms up and the temp sensor quits giving the ECU input. At this point
the microswitch should continue telling the ECU to continue diddling with the by pass solenoid. BUT if it isnt working the ECU quits working the solenoid and
the car idles like kakka and or dies unless throttle is applied to open the throttle body intake flap.
On my 84 there is a black plastic on the backside of the throttle
body... not a microswitch as shown in the my manual. seems to be adjustable by
loosening a hex head screw. this "switch" has a booted connector plugged into it
that I havent remove yet so I dont have any idea how many wires are in there.
So what other nifty transducer inputs to the ECU (if any) are there for this
function that I may have missed due to useing a crappy manual (Chilton). I havent had time to hunt down a Haynes.
Damn! I am haven fun! I wonder if dual solex carbs could be mounted on this thing!


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