[Bill_Hancoc]

I had a smilier problem with my Lexus. It appeared to be an electrical problem and i had a bunch of sensors and the like replaced to no avail. Upon further engine examination i found a lot of carbonization (i think thats a word) on the throttle body blocking air flow when the engine was cold (this continued into the summer not just a winter problem). Once the engine would heat up it would run fine. Try checking the throttle body for and signs of corruption or the above mentioned.

Hope this helps