Stumbles at 45-55 mph when giving it a little bit of throttle
I have a stock 289. My IAC steps average between 5-7 at operating temp (over 170 degrees).
The issue I am experiencing is that when I am cruising at about 55 mph in 5th gear and I give it a little fuel to slowly increase speed, I get a stumble until it gets up to about 65 mph or so. I am looking at the data log and my AFR consistently goes to 10.4 or so.
Here is a link to the data log. In this log I felt the stumble every time the AFR went down to 10.4.
https://drive.google.com/file/d/1oODOmMcD2s9G_P2EZ_uPJKMWiWAe7a8I/view
I am reading some information about a possible firmware update that might address some accelerator pump issues, but I can't find anywhere to download a firmware update.
So far I have tried changing the Accel Pump 170F setting. It is currently at 4.7 and moving it up and down by about 10-15 does not seem to fix the issue.
There is a software update topic in the Members Section. There you will find information of how to receive the latest software.