Stalling when cold
 

I'm still fighting an intermittent problem. The car will sometimes stall when it is cold. It will start up fine, run a little while then quit. It starts again and may stall again. After about 2 miles of driving (with your fingers crossed), it's fine.

I finally got a CEL. It's a code 37 for the left side O2 sensor. Does anyone know if this could cause stalling? I thought it would just affect the emissions. I am thinking that I have just discovered a new problem and replacing the O2 sensor won't fix my real problem. Thanks for any opinions.

When the engine is cold so is the O2 sensor. The engine operates in 'open loop' at that point, using a fixed set of parameters. So, no, an O2 sensor won't cure cold idle stailling.

Do the usual checks - vacuum leaks, crudded IAC and/or idle air bypass valve, etc.

Can you elaborate a little on the "usual checks." I have attempted to clean the IAC by cleaning the throttle body. Is there a better way?

I assume for vacuum leaks I should do a visual inspection.

What about idle air bypass? What exactly is that?

These are probably dumb questions, but I appreciate any help. I have been shot gunning this thing for months. I have already done what I considered the usual things:
Plugs
air filter
fuel filter
All 6 coil packs
Fuel system cleaner in gas tank
Throttle body cleaning
Replaced/reset TPS

The frustration is extra high because I just spent $700 having a solenoid replaced in the trans (TCU code 13)