2001 Ford Taurus

This past winter my wife’s 2001 Ford Taurus (160,000+ miles) would crank but would not start in the extreme cold weather. This would sometimes be the case for days until the first thaw and then the car would start on the first try. In our desperation we flushed the radiator, replaced the battery, spark plugs and wires, the fuel filter, added dry gas, added fuel injector cleaner and replaced the pvc valve (we also replaced 2 tires, why not). Our mechanic told us that each item was due for a change but $600 later and the problem has not been resolved.

On one occasion since the repairs our check engine light has flashed indicating an engine misfire (lasted about 5 minutes and has never happened since) and the first reasonable cold morning we have had (about 35 degrees over night) and the car would crank but not start. 3 hours later when the sun hit the car and the temperature started to rise the car started on the first try. i have been told that this can be caused by about one million things but I would like to narrow it down before I pay for my mechanics new yacht.

Any help or suggestions would be greatly appreciated.

How does the car know when it’s cold? The engine coolant temperature sensor, and the intake air temperature sensor, tell the engine computer so, normally.
The fault can be in one, of two areas: 1. These sensors are misinforming the engine computer, and as a result, an added shot of fuel isn’t being sent to the engine for cold start; 2. The sensors are true, but the engine computer isn’t ordering added fuel, or, the order isn’t being carried out.
Finding out which one of these scenarios applies, is what you employ the mechanic for.