1990 Throttle hesistation

[XfireZ51]

Chuck,

Reading what you've done by incrementally moving the throttle is this:
As you approach 1.6-1.9%TPS(just off idle) the ECM transitions from idle to run. What's happening is that it goes from using a static SA for closed throttle to SA in the spark tables. When tuning, you try to flatten that area so that you don't get surging that seems to be happening. May need to look at that table. At the same time you are also transitioning from single to double injector spraying since the ECM is transitioning from a Closed Port VE table to an Open Port Throttle VE table. OTOH, I doubt that your throttle movements are so fine that you are always are always at that point. In the stock calibration, there is a slight delay built into the turn on of the secondary injectors, most likely to give the secondary throttle plates time to open. Also, acceleration enrichment may need a bit more fuel to enhance tip-in response.