'84 Supra idle too low and dies.

[Tim_C.]

A friend owns it. It is all original parts, with 147K miles, manual trans. ALLDATA says there is no way to 'adjust' the idle. It is around 400 RPM, and then dies at the stop light. One cylinder might be a little low on compression. The plug builds up with oil. I suspect that is the main issue, but it seems there should be a way to bring the idle up a touch.
I see some cracks in the hose to the TB, but they don't seem to be leaking. I need to check with some TB spray.
My plan is to
1. Clean the air flow sensor, and the TB by spraying it with TB cleaner while running.

2. Reset the TPS.

3. Check the cracks for leaks.

Can someone let me know if I shouldn't do any of the above, and or what else I should do?

[Jeeves]

Look for a flat blade screw near the throttle body, it'll probably be in a nook or cranny. Stick a screwdriver in the hole and turn. See if that works.

[Tim_C.]

Is it the one where you need to pop-off the little plastic cover? I think it is an idle mixture screw, and I tried that with no change. It was adjusted almost all the way in. Like 1/8 of a turn off the seat.

I thought it was odd there would be no change by turning it out, but it did nothing.

[Jeeves]

The Idle mixture screw is the one built into the air flow meter, which you'd find near the front of the car, right after the air filter.

Except I can't confirm the locations for any of these things for your year. Hell, I don't even know if it had a screw for the mixture.