4.9 no iac first start help

[twinturbor]

I made a forming die for the ball sockets on the manifold and just used the old compression sleeve. And in answer to your previous question, I have the white shielded wire going to the pip on the tfi

[twinturbor]

I just confirmed that the voltage is rising on the leading edge of the vane. I'm not sure if its the same on the v8 models. Am I correct in saying that when my voltage is climbing that would be the rising edge? All other tfi posts state that it needs to be the falling edge but that's seems contradictory to my situation. When its on falling I can't see my timing but on rising I do.

[slow_hemi6]

Hang on, I am a bit lost did you ever do anything about not having Q16 installed?
Rising or Falling is not referring to the signal at the sensor. It is referring to the signal at the processor pin. Depending on how the input hardware is done/used there could be one or more inversions of that sensor signal.

[twinturbor]

I left my unit set up for tfi and I'm going to give it one more try with this setup. If it doesn't work then I will send it out for the direct coil control. But I have to try it one more time like this before I give up on this configuration. I will need to do the direct control in the near future for high boost but I want to understand this setup so I might be able to help someone else in the future. I'm a trainer at work and I always have the answer or the steps to get there, so I'm trying to learn all I can about this stuff as well. I don't accept failure well.lol

[slow_hemi6]

As I said back on page 2, I don't think your ecu has ever been set up for TFI. TFI requires a Q16 as well.

That is correct. The first thing you notice is that there is no Q16 installed. That means the board is not built for TFI or High Current coil switching. I would say it's just a std MS2357C.
On DIY's website when you look at that product it says in the description,

5 volt ignition output (JS10 jumpered directly to pin 36) for EDIS, Bosch 124, or GM HEI ignition control
Slot for installing a BIP373 (not included) for direct coil control

So that explains everything really.

[twinturbor]

My ecu runs the tfi as of right now but I'm still wondering if rising edge means going up in voltage. I commanded 12 degrees and the timing showed perfect. I just wanted some clarification on the rising edge vs falling edge

[hybrid]

Rising edge is voltage on the way up. Falling edge is voltage on the way down.

[twinturbor]

Thank you. That's what I needed to know. I can move forward now

[slow_hemi6]

Rising edge is voltage on the way up. Falling edge is voltage on the way down.

At the IRQ pin.

[hybrid]

Rising edge is voltage on the way up. Falling edge is voltage on the way down.

At the IRQ pin.

Yes I should have clarified. So depending on hardware setup, the actual setting could be the opposite of what is seen at the sensor.

[twinturbor]

Just wanted to say thx for all the help. I finally got this beast up and going. I put it aside for a while but now Im just down to tuning for boost.