odd behavier
 

I have a 1997 850 and when the temp goes down to 45 and below the car has a hard time starting. It will start then die and this happens for up to 30min then it starts and runs fine. Is there any reason for this to happen.

You have to do some tests. It could be alot of different things.
cars need Fuel, spark, air, and compression to run. Begin by looking for DTC (Diagnostic trouble codes) with a scan tool or code reader. You may find some issues with the mass airflow sensor. next look at the plugs- if youre cranking on your car for thirty minutes they will probably be wet from flooding (which is probably a contributor to the starting issues) and while their out go ahead and do a compression test. if all that goes well test for spark. will those results it will be alot easier to come up with whats going on.

I would suspect a bad coolant temp sensor sending a bad signal to the computer so the engine isn't getting enough fuel to run, isn't rich enough. To be able to start, restart and restart for five, ten or more minutes and not flood the vehicle it almost has to be way to lean.

Ok two both my replies its not flooding I have checked the plugs before,like I said it only does it at low outside temperature,if it is warm it fires right up. So where would the temp sensor be at and ill check it out. I want to get it ready for my son to use in Wyoming.

Just under the thermostat.

I agree with the prince.

And to second guess myself it could also be a fuel pump relay that is kicking out right away. Gives you enough fuel to fire up and then turns the pump off. It's pretty unlikely but it's worth mentioning. Usually they heat up and fail for a while and if you let it sit and cool off it will restart.

You could try the "paper clip" trick of jumping the fuel pump relay when you are having the problem. Pull the relay, pop in the paperclip and see if it starts and runs ???
Fuel pump relays are a weak link and there are many threads on doing this jump.