SOI?

[Power Hungry]

Cody... don't worry about your post. It's not bad information as such, just a difference of opinion on how reliable you find the data bus to be. I certainly don't disagree with the theory of "garbage in, garbage out" but I would ask you to consider for a second that if the PCM can't produce consistently reliable data pertaining to the vehicle's operation, then what's the point of it in the first place. Granted there are mechanical aspects that the PCM might not be able to compensate for:

• Timing gear/chain wear affecting the CPS output
• Bad CPS
• Worn injectors/weak solenoids
• Weak IDM

However, the only thing that's going to tell you if those (or other) items are causing problems is a scope, a breakout box, and time.

Because I expect the PCM to generally work from reliable data, I tend to trust the data being provided via the OBDII port. After all, this is the same data that the PCM is using to generate all its outputs. Is it the end-all, be-all of tuning? Of course not. But it does provide valuable data in relation to changes on a specific vehicle and I can use it to determine just how much more or less aggressive certain files are in comparison to each other. In the grand scheme of things, is 2 or 3 degrees of SOI or .3 ms PW going to make all that much difference when there are tunes out there that more than DOUBLE the SOI or Injection PW? Probably not.

Like anything else, it's a tool that provides information. As I see it, the more info, the better.