I was adjusting my rig yesterday, I used the 450ma +/- 30ma current draw
method to set the idle control valve. Adjusting the bypass screw on the TB
adjusted the ma draw of the unit (an indication of how hard it was working)
but no change in idle speed. I conclude that the idle control box knows how
fast the engine is going and regulates the amount of air the valve bypasses
to regulate the idle speed.. The ONLY was the idle control box knows how
fast the engine is going is through its connection to the the distributor
hall sensor. If the engine runs then the hall sensor works...

So ... There is a wiring problem that doesn't allow the hall sensor signal
to get to the idle control box. On my rig I had a corroded connector (white
wires with a yellow connector, above the thermostat housing) it had a
resistance of 50-60 ohms, enough to show continuity but attenuate the
signal.

Is there a prize :-)

D

On 20/07/09 12:25 AM, "Benny boy" <huotb@VIDEOTRON.CA> wrote:

> (1984 van) Ok, van run super fine but!!!! Here is a funny one... i rebuilt
> an engine and we have a problem Houston, very low idle, around 500-600. No
> way i can raise this one easily with TB. So, let's see some suggestion!
>
> NO, it,s not idle control box, NO it's no timing, NO it's not ign unit... No
> it's no ECU, no it's not temp 2 or OS. I think I know the answer but i'm
> waiting.
>
> It's a fun game.
>
> Hint: How can it be TB?????
>
> Ben