Okay, then I do have to go back to the AFR again and recheck what I input for the intermediate settings. I may have to add more air to take the readings back the other way. That could explain why it is dropping dead on me. Too rich when warm and it could be choking itself out.
Right now the IAC is showing 4-6 on the programmer screen. As for the the backstory on the IAC, apparently, as sold and delivered, my brand new TBI unit came to me with the throttle plates totally closed and the IAC inoperative. Unadjusted like that, one of the major issues is that the throttle plates are way over centered and it takes a lead loaded shoe to put enough pressure on the acc pedal to get it to move. Fought that problem for years in ignorance until someone posted a video of that neat little screw at the front of the injection body that you can barely see the head of, and what has to be done with it. Turns out, literally, that it came from the factory backed out so far that the screw point had NO contact with the cam on the throttle shaft. i forget how far I had to turn it in to get the IAC to come alive but a full turn and a half is a good guess at this point. Buried as it is, you cannot visually observe any changes that adding or subtracting to how far in or out the screw is sitting have accomplished.
The other thing is, at least for my van, accessing that screw is beyond hard to difficult. Van engines are not situated like car engines, When you open the hood, you discover that they are recessed back under the dash to a major degree. With the doghouse off and the engine exposed, my mill is so close to me that I can put my hand on the timer without taking my eyes off the road. At one point I was actually doing test laps with the motor uncovered. Major noise factor but high on the fun meter if you dig being that close to the action.
That being the case any adjustments to the idle screw have to be done with the engine off. Just too much of everything in the road and all of it HOT when the engine is running.
So it looks like I get to go back at it again tomorrow.
Nick
Right now the IAC is showing 4-6 on the programmer screen. As for the the backstory on the IAC, apparently, as sold and delivered, my brand new TBI unit came to me with the throttle plates totally closed and the IAC inoperative. Unadjusted like that, one of the major issues is that the throttle plates are way over centered and it takes a lead loaded shoe to put enough pressure on the acc pedal to get it to move. Fought that problem for years in ignorance until someone posted a video of that neat little screw at the front of the injection body that you can barely see the head of, and what has to be done with it. Turns out, literally, that it came from the factory backed out so far that the screw point had NO contact with the cam on the throttle shaft. i forget how far I had to turn it in to get the IAC to come alive but a full turn and a half is a good guess at this point. Buried as it is, you cannot visually observe any changes that adding or subtracting to how far in or out the screw is sitting have accomplished.
The other thing is, at least for my van, accessing that screw is beyond hard to difficult. Van engines are not situated like car engines, When you open the hood, you discover that they are recessed back under the dash to a major degree. With the doghouse off and the engine exposed, my mill is so close to me that I can put my hand on the timer without taking my eyes off the road. At one point I was actually doing test laps with the motor uncovered. Major noise factor but high on the fun meter if you dig being that close to the action.
That being the case any adjustments to the idle screw have to be done with the engine off. Just too much of everything in the road and all of it HOT when the engine is running.
So it looks like I get to go back at it again tomorrow.
Nick
