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I've got an 05 Base 5 speed with a k20A3.
I have recently installed an RBC intake manifold, IMG, Type-S throttle body (K20A2) with brand new TPS (made sure to rewire it properly).
TPS is working and reads perfect. I deleted the IACV and disabled it in KTuner. Used a block off plate to close it off. I looped the coolant line.
Quadruple checked for vacuum leaks, there are none. However, the idle sits between 480-750rpms. When the rad fans kick in the engine almost shuts off.
No matter how many times I try to relearn the idle, it does not improve it. I have reset the ECU multiple times. I've tried switching the map sensor from the throttle body to the manifold and am using the ktuned plug for the open port that came with my throttle body adapter.

What would be the best way to deal with the low idle in KTuner? I'm hesitant to mess with the idle adjust screw on the throttle body.

Extra info:
I have a brand new primary o2 with the secondary blocked off and disabled.
I've tried misting the engine bay multiple times, this does not effect idle or reveal any vac leaks.
I have pinched the vac lines one at a time to check if there are issue with those creating this idle problem. None of them effected the idle at all.

The throttle adjustment screw and ignition timing are the only way to control idle when you're not using an IACV. You have access to adjust idle ignition timing in the software.

Thanks for the swift reply! I was in looking at the idle ignition timing but there was a section that advises to not touch it (I believe it was under an advanced section though). Given the circumstance, which would you advise to alter first? The car runs fine under load but at idle it drops too low and at intersections it sometimes cuts out.

You want to alter the Advanced Idle Control section as needed until you reach your target and/or adjust the throttle screw as needed.

Thanks again! I was able to get it to idle at a desirable RPM by adjusting the parameters under advanced idle control. However, the surging is more prominent and appears to be related to unstable MAP readings with AFR fluctuating alongside it. Going to check again for an exhaust leak and have ordered a new MAP sensor. Going to go bother CRSX about this one.

what is the purpose of removing the IACV?

That could be caused by fueling too, going from rich to lean, etc.

Fueling is what I'm looking at next. My MAP sensor fluctuates with the fueling but appears to be within an acceptable mBar range (315-350). I'll know for sure when the new map sensor gets here. After a 20 min run, the only code my car temporarily throws is for the ECT sensor, so I've ordered one of those as well.

The reason for IACV delete is because the IACV i had with the K20A2 throttle body I picked up was in rough shape and i only drive my car in the summer. So when I did the RBC install with Type-S throttle body on my base i just did the IACV delete with block off plate.

I'm hoping to troubleshoot these smaller issues and eliminate any potential sensor and fuel problems because shortly i'll be installing a K24A1 head with S2K valvesprings, Type-S retainers and K20A2 cams and exhaust rockers all around (vtec killer). I don't live near anywhere to tune and it takes 2 weeks to get any parts I may need. Hopefully the only thing I will need to do after the install is pay for an e-tune. Who would you recommend for that? I see turbogixxer has posted on here. I was hoping to find a basemap for vtec killer to use before starting it up and getting an e-tune.

I would definitely talk to Turbogixxer about e-tuning!

I'm trying to do a IACV delete right now, where do you loop the coolant lines to?