1998 V70 Starting Problems

I could really use some help before I give up my wallet to the Volvo Service Department. The problem started during our cold weather (<20 Deg F). The starter cranked over fine, and it would fire once, then nothing. Each time I let off the key and tried again it would do the same thing. I tried until the battery went low. I recharged the battery and tried again, no luck. Went out the next day and it started immediately. I have replaced the plugs and wires. Seemed OK for a week or so then it did it again. I found when it did this, that if I alternately pushed the pedal to the floor, tried it, let off the pedal and tried it again a few times I could usually get it to start. Once it started, it would run rough for a couple of minutes then would be fine. I have since noticed another symptom I feel may be related. Whenever I have had this problem, I notice the (radiator) cooling fan is running, even after I remove the key. When I finally get it started, the climate control fan comes on full blast right away (it usually does this after the engine has warmed up). It seems that if the cooling fan is running when I shut the car off after a drive (keep in mind it's well below freezing outside), the next time I try to start the engine cold I have the problem. If the fan shuts off with the engine, the car starts fine the next time. Questions:

Does the engine temperature sensor tie into the air/fuel mixture for starting?
I suspect I may have a vacuum leak (P0192) but would this lead to intermittant problems like this (Iv'e had this error for a long time with no apparent start/run issues)?
I have searched this site and never seen a temperature sensor affect start/run. Has ANYONE ELSE HAD THIS SYMPTOM?
I'm going to try finding a vacuum leak today before the next snowstorm arrives, but my gut tells me this is not the solution. HELP PLEASE!!!