Shadrock

I read the threads earlier about ML320 not starting, and all suggested the CPS change. I have changed the CPS, the fuel pump (along with filter and wires), the battery, and changed the ignition switch. It originally would stall and not restart, so we began the CPS route and ignition switch. It no longer stalls, but won't start if the temp outside drops below, say, 40 degrees F. Hence the battery, fuel pump and filter. I should mention that it cranks until forever, just won't turn over. As soon as the sun warms it up to above 40 outside, runs like a horse! Any other suggestions? I'm really frustrated...Thanks if you can help!