I have a 96 honda accord lx with 200k. When it gets below 20 degrees it will not start. I have done a tune up,replaced the main relay, ecm, coolant temp sensor, distributer, and once it gets below 20 degrees it still won't start. If I put a heater inside the car it will start after about 10 minutes. Any ideas?? Thanks.

 

About the only thing left, and inside the car, is the ignition switch.

 

maybe you have a broken circuit somewhere, and with all things, when temp goes down, things (in your case a wire) shrink, and when temp goes up, things expand.