DTC's 122,157,Possible Restriced Exhaust,Mal.Fnc.02Sensor,Int.Man.Leak?
The test results are all within range, so that's good. The MAF sensor is slightly high, but that voltage can vary due to load and ambient temp.
(Assuming that everything else is in good working order as you stated)
The water coming out the exhaust is "normal" to a point. A lean running engine will produce more O2 (according to my G1 instructor). With more 02 available in the exhaust, the possibility of increased formation of H20. However, if there is back pressure in the exhaust, and then a spot where pressure drops rapidly (i.e. a pronounced restriction in the exhaust), the temp. of the gases will drop accordingly. With the temp. drop, can come the formation of excess water in the exhaust due to condensation. Normally, the heat of the exhaust system will prevent formation of water droplets and keep the H20 in the form of steam. However, under normal conditions, you will only see this steam in very cold climates where it condenses as it reaches the atmosphere outside the exhaust system. On a normal car, a few drops here and there are normal, but water that seems to come in a constant stream indicates that something is causing the exhaust gases to cool down too much before exiting the exhaust system. One things that comes to mind would be a plugged CAT, but it could be any one of the components in the exhaust. For instance, if your exhaust output is far in excess of the exhaust systems capability to handle, then this too will cause your problem.
With regard to engine coolant being the cause of the water in the exhaust, from what I've read on the net recently, you would be smelling a distinct "sweet" smell from the antifreeze, and you would be loosing coolant from the engines cooling system at a rate that would be noticeable (under most common conditions!).
A more realistic problem would be that the intake manifold is leaking both coolant and vacuum. The coolant loss would be hard to detect, and vacuum would get slightly better, or slightly worse (+1-3 lbs.) as engine warms up, depending on how the seal between the intake and head are reacting to engine heat. In this case, replacing the intake manifold gasket and torquing the intake manifold PROPERLY will prevent future leaks. I believe this was a TBS for service techs. If the intake manifold is not torqued properly, it WILL leak!
Best to do a back pressure test of the exhaust system at the O2 sensor.
As far as the DTC's of 122 and 157 for low voltage to the MAF and TPS, I think you've determined that these components and their supplied voltages are good.
You should test the O2 sensors while your at it, as they too can contribute to the problem if not functioning properly.
Also, there is an adjustment (on mine anyway) of the TB for the IAC. Under a small rubber plug is a torx adjusting screw. It works in relation to the IAC's inlet air feed. I adjusted mine by first determining its position. Started that engine, and at operating temp., adjusted the screw like this:
Move throttle linkage by hand to raise rpm to between 1500-2000 rpms and then let go.
listen for rpm to drop smoothly back to idle.
If RPM is held up at some point and then drops to idle, then adjust the screw to eliminate this uneven transition in RPM.
After re-reading your previous post, you mentioned that the top radiator hose get really hot, but that the engine is not running hot. A lean condition with a could cooling system is my guess. Cylinder heads are getting very hot and causing problems with combustion. This would be in line with an intake manifold gasket leak, and possibly a thermostat that does not have a bleeder orifice positioned at between 12 O'clock and 3pm.
Geezshes, this is a really long post so to sum things up:
First things first,
1. check the thermostat for proper position and that no air is trapped in the cooling system.
2. Since you have the thermostat out, remove the intake and replace the gaskets.
3. With the intake out, check the fuel rail pressure (too low will cause lean condition).
4. Your DTC's of 122 and 157 are a result of the PCM trying to adjust fuel trim that was out of range of the sensors. A lean condition is due to un-metered air getting into the intake system. That's why the intake gasket replacement. You will have to remove and reinstall everything in the intake system and this will help get ride of any unknowns.
5. Check the exhaust and 02 sensors, as they are the other half of the the intake system.
6. While you have the intake manifold off, remove and reinstall the CPS just to be sure its not off a tooth. I know there is a fudge factor, but get it exact.
7. With the intake and IC tube off, pressure check your IC cooler, and reseal the IC tubes. I used plumbers Teflon tape (thick), and some spray adhesive to hold the tape in place. Apply the tape to the male ends of the IC components. Small wrinkles will not be a problem after tightening down. Be sure to re tighten all the joints after waiting 10 minutes.
8. After testing/reassembling everything properly, start and warm the engine to operating temp. Then do an idle relearn by cycling from park to drive, and waiting in each for idle and smoothness to adjust, with out touching the gas pedal.
At this point, your problem with lean banks and poor idle should be gone.
Clear codes and perform KOER, and or drive the car for awhile and see how it runs, and if any DTC are generated.
I took the console out, and the plate around the shift lever and I found about $3.00 in change wedged down in there. 
