Unexpected trip to the store tonight. The codes are:

P0174 - Powertrain - System too Lean (Bank 2)
P0155 - Powertrain - O2 Sensor Heater Circuit (Bank 2 Sensor 1)
P0171 - Powertrain - System too Lean (Bank 1)
P0455 - Powertrain - Evaporative Emission Control System Leak Detected (gross leak)

It has also started dying on me as I come to a stop.

I looked at a couple values - spark advance was 10 degrees at idle and upon acceleration progresses up to about 40 and drops back with the shift. My temp sensor is often showing very hot, but the values are 88-91 degrees Celsius. I tried switching to F, but it hasn't worked to make the switch yet.

 

I have no way to really prove it but I feel that all these codes are related. Trouble shooting of the evap system seem to be very complicated. So perhaps you can try something else:
there is a single vacuum line from intake manifold to the Evaporative Emission Purge Solenoid. Disconnect it and plug the portion that goes to the engine (to eliminate a vacuum leak). Clear the codes and drive as normal. After a couple of drive cycles (Key On, Key Offs) it will most likely set back the evap code again (since the system is not going to work as designed), but if it sets any other codes for the "System too Lean" you will know that you have a massive vacuum leak elsewhere in the system and it is separate from your evap system problems.
I'm not familiar with the apps you listed, but look for the "Freeze Frame data" in there. When the computer sets a DTC code it will record a snapshot of what conditions the engine is running under. What we need is Short Term Fuel Trim (STFT), Long Term Fuel Trim (LTFT), Engine load, Engine RMP, and anything else it recorded.

 

I did some research to better understand how to do the freeze frame. I tried it and the data as all absurd - like coolant at -40F and fuel 100% on all counts. Here is what I had taking a screen shot at idle, in park and motor hot after clearing codes.

Fuel Trim bank 1 Long term = 12.5%
Fuel trim bank 1 sensor 1 = 3.12%
Fuel trim bank 1 sensor 2 = 2.34%
Fuel Trim Bank 1 Short term = 2.34%
Fuel Trim Bank 2 Long Term = 10.94%
Fuel Trim bank 2 sensor 1 = -3.91%
Fuel Trim bank 2 sensor 2 = -3.91%
Vacuum -12.16 psi

Moving about 15 mps O2 sensors

O2 volts bank 1 sensor 1 0.08V
O2 volts bank 1 sensor 2 0.78V
O2 volts bank 2 sensor 1 0.18V
O2 volts bank 2 sensor 2 0.46V

Fuel Trim stopped in drive:
Bank 1 Long Term = 12.5%
bank 1 sensor 1 = 2.34%
bank 1 sensor 2 = 3.12%
bank 1 short Term = 2.34%
bank 2 long term 11.72%
bank 2 sensor 1 = 2.34%
bank 2 sensor 2 = 2.34%

Last night, before I reset the codes, the vacuum was -9.81 or something like that. Is this helpful? I did find an add-on for Mitsubishi I will purchase later and see if I can get better information.

 

It helps a little. Think of Fuel Trims as how much fuel delivery deviates from what computer thinks is "normal". If you have a positive fuel trim, that means computer has to add more fuel to the system to balance the amount of air entering the system. Short term values are quick response (stomp on the accellerator, etc.), Long term is how the system behaves in the long term with fluctuations leveled out over time. When you clear codes all values are reset to 0 and computer "relearns" what the current engine does and adjusts all values to make it run optimally. As you can see, your Long term values are 11 and 12% (i.e. adding 11-12% more fuel compared to how much air computer "thinks" is getting through the MAF) and your short term trims are 2-3%. This means computer still did not find equilibrium and keeps calling for more fuel. Your long term values will keep going up and when they hit 24-25% it will set Check Engine light.

Looks like you have live data reading capability, so you can try this:
with the engine running, pull up the LTFT and STFT for both banks; note the reading; stomp on the accelerator pedal. If your fuel trims momentarily switch to negative values at wide open throttle and then go back to positive when you let go, that means a vacuum leak.

Try to block off the vacuum hose to the Evap Solenoid and check values again. If they go down (both short term and long term) than the vacuum leak you are getting is coming only from the Evap system. There are many ways to try to find a vacuum leak. You can also try spraying some propane (or carb cleaner) around the manifolds and watching the fuel trim values. As you do that if the fuel trim values change (go down) than meanss the vacuum leak in somewhere near that area. This is because propane is fuel and the extra fuel will compensate for the extra air that is getting into the engine in that trouble spot.

One more thing - you sound like a fellow that enjoys understanding thing and not just swapping parts. Check out this video on youtube - it explains the fuel trims and how to use them in diagnostics. The guy is very good at this and it will help you to understand how the computer works its "magic".

 

Thank you. I will certainly take time, as soon as I have some, to go through the video. And you are right, I really like learning and I am a global learner, wanting to understand more and more of the big picture and how everything interrelates. This morning I got new codes pretty quick and I played some more with the freeze frame and I finally got some data that was reasonable. The first one, the coolant temp was way low and the second was more in line with what the live stream shows. Here are the screen shots of the freeze frames I took.

Number 1
Number 2

Occasionally it is smooth under a load, but most often it surges. I am going to look more closely at the vacuum lines this weekend, if it is above freezing here.

 

Well, the good news is that your LTFT are staying at around 12% and not going through the roof. This means (most likely) that it is a moderate vacuum leak. If you try to isolate the Evap circuit and it does not improve, you may have additional vacuum leak. On the channel I recommended you can look through other videos and you'll find one with using propane to find a vacuum leak. I can't remember which video it, so you'll have to find it on your own. I have tried to do it on my vehicle and it works pretty well (with practice).
As far as the rusted out filler neck and evap lines. I guess your vehicle came from the rust belt? Is it possible to scour junk yards to find a replacement?

 

Keep us posted, I can't wait to find out what made your antifreeze turn black.

 

keep us posted as I can't wait to find out what turned your fluid dark.

 

I tried spraying starting fluid around the intake and vacuum lines with nothing turning up. I played a little more with Torque Pro on my OBD and my vacuum seems to be strong while driving. I will keeping watching. And still no real strong ideas on the black fluid. My plan is to continue driving around town until I get my tax return which I will use a little to replace the fuel filler/evap lines and the one O2 sensor and see where I end up then. Thanks for the help/advice.

 

I just realized I never updated this. After replacing the fuel filler lines I replaced the fuel pump and filter. The motor smoothed out and I regained power on acceleration. Before pushing the gas down all the way just revved the motor and seemed to disengage the transmission. Now it accelerates well.