What is the set screw for?

[goatfarmer]

1990 T4r auto/4x4/v6
Approx. 2 years ago trans and engine shop rebuild
Approx. 1 1/2 year ago had shop tune up. I have replaced rotor, plugs, oil and filter over the years but have always taken to shop for a tune-up. This time decided to do it myself.

What does the set screw do?

Within the past week replaced the accelerator cable and a tune-up; plugs and wires, rotor, oil and filter, air cleaner. Without removing the throttle body I did remove the ducting and clean the bore. Before adjusting the timing I marked the position of the distributor retaining bolt then used the jump wire T1-E1 and set the timing only to find the new mark is approx. 1" off to the original?

Starts and runs fine around 1200 rpm then drops to 650 rpm when the engine is warm but then as I let the engine continue to run it eventually stalls but I can then turn the ignition and it starts and runs fine w/ no stalling??

If understand correctly with the later model Toyota there is a procedure for resetting the idle would it apply to 1990?

Comments/Suggestions appreciated!!

 

[SaulG]

1. When setting the idle speed make sure that:
a. Air cleaner is installed.
b. All vacuum hoses are connected.
c. Make sure that all fuel injection wiring connectors are fully plugged in.
d. Engine should be at normal operating temperature.
e. All accessories should be turned off and the transmission in neutral.
2. Connect a tachometer to the engine

NOTE: Never allow the tachometer terminal to contact a ground as this could cause damage to the ignition system. Some tachometers are not compatible with this ignition system, so please confirm the compatibility of your tachometer before connecting it to vehicle.

3. Run engine at 2,500 rpm for about 2 minutes.
4. Set the idle speed by turning the idle speed adjustment screw.
Idle Speed Adjusting Screw


Idle Speed: 800 rpm

5. Remove tachometer.

 

[goatfarmer]

Sorry, not sure why I did not receive response notification, I thank you for the input!!.

 

[SaulG]

You fix it ?