hello all- love the forum and it has been most helpful! hopeful that someone can help me out. i have an '01 disco w/ 110k miles- regularly serviced-- i live in tampa, fl and it has been cold the past few weeks (for florida anyway). Every time i try to start my truck when its VERY cold in the AM, it will not turn- it sounds like it is cranking nicely, but will not turn over--had battery/alt checked and is fine--baterry only 2 mos old-- had to have it towed to my mechanic and he replaced 3 out of 4 O2 sensors (one was on back order, but coming this week) it has been starting just fine until our latest cold front... (35F low) could this last new O2 sensor seriously be the culprit and if so, why has it started w/o 4th new O2 sensor on warm mornings? thanks for any help!!!