Possible fueling issues?

DIGItonium

No AFR gauge. I need to find something useful and not crazy expensive to integrate to my dash. Future plans is for a HKS boost controller (replacing the Hallman Pro RX MBC) and mount the display along with something like an AFR or combo display to the dash.
[EDIT] Found it: http://zada-tech.com

As dumb as it sounds, what would cause it to run progressively richer? So this is what I'm seeing after 45k boosted miles:

• On the passenger side, where I've already noticed some minor oil residue on the turbo hot side (no smoke), the vacuum hose to the throttle body has some residue, and the same for the PCV. Valve cover seal looks good. Driver side looks clean, but the valve cover is starting to show some minor leak.
• Idle isn't perfectly smooth, but I'm going to attribute this to 45k boosted miles without maintenance listed below.

I do plan on doing some maintenance work in the next couple of months. I'm putting together a list of things to do once the throttles and intake plenum is removed:

• Replace VR38DETT OEM Spark Plugs
• Replace injector seals and o-rings - Do the injectors use stock rings and seals?
• Replace throttle and intake plenum gaskets
• Replace PCV
• Clean throttles, sensors, etc.
• Replace air filters
• Clean and lubricate BOV
• Possibly replace or extend some vacuum hoses

This is just the engineer in me asking since I'm not really a mechanic, and I may start learning how to do some of this stuff with no tuners around. Nearest is probably KC or Dallas. Although there's 65k total miles on the car, I'd love to get it tuned. Just too much on my plate, and it has been a rough year as a new homeowner. The Z has been put in the backburner for the past 2 years.

-Phuong

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