I'm fairly new to tuning, and have been following a document referenced in several places (forums, etc.) to get started. The first part of the procedure basically includes disabling MAF, and LT fuel trim. From there, the ST fuel trims are used to make updates to the primary VE v. MAP v. RPM table. Assuming that's a valid procedure, my issue is that I spent an hour chasing my tail. I'd copy the ST values, and use them in a 'paste special -> multiply %' function in the editor. After several iterations of that, I'm still pretty much seeing the same ST values in the same places (yes, I flashed tune updates)!? What gives?
I've installed a wideband o2 sensor right across the header from the primary o2 sensor. The wideband indicates lean (~15..16 afr) while the PCM is generally pulling fuel (negative) trims. The basically means there's a big mismatch there right? WB thinks lean and primaries think rich?
I can post my tune and scan logs when I get home tonight. At this point, I'm mostly looking for some validation that my approach and understanding is sound.
TIA